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请问哪里有在线能用的Access或SQL Server数据库?

2023-07-19 22:40:45
共3条回复
余辉

我发给你的那个数据库就是用于mdb的,很好用:

//初始化记录集:

CADODatabase m_pAdo;

CRecordset m_pRs;

InitDatabase()

{

CString strConnection = _T("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=CMyData\Database1.mdb");

if(m_pAdo.Open(strConnection))

{

m_pAdo.Execute(_T("delete from OLETable"));//清空该表

m_pRs = CADORecordset(&m_pAdo);

m_pRs.Open(_T("OLETable"), CADORecordset::openTable);

}

else

{

AfxMessageBox(m_pAdo.GetLastErrorString());

DWORD dwError = m_pAdo.GetLastError();

}

}

压缩数据库--数据库文件不可以事先已经被打开或被正在被使用--否则会出错

MyCompactDataBase(const CString& strFile)

{

CString strCompactedDBConnection;

CString strConnection;

//CString strCompactedDBPath = _T("CMyData\SampleDB.tmp");//临时文件--用于转存

CString strDatabasePath;

if(strFile.IsEmpty())

strDatabasePath= _T("CMyData\LabResult.mdb");

else

strDatabasePath=strFile;

CString strCompactedDBPath = strDatabasePath+_T("s");

strCompactedDBConnection.Format(_T("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%s"),

strCompactedDBPath.GetBuffer(0));

strConnection.Format(_T("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%s"),

strDatabasePath.GetBuffer(0));

if(CJetEngine::CompactDatabase(strConnection, strCompactedDBConnection))

{

::CopyFile(strCompactedDBPath.GetBuffer(0),

strDatabasePath.GetBuffer(0), FALSE);

AfxMessageBox(_T("压缩数据库成功!"));

DeleteFile(strCompactedDBPath);

}

else

AfxMessageBox(_T("压缩数据库失败--请确认压缩目标未正在使用"));

}

备份数据库:

BackUp(CString &filename)

{

if(!filename.IsEmpty())

{

if(CopyFile(_T("CMyData\LabResult.mdb"),filename,FALSE))

{

AfxMessageBox(_T("备份数据库成功!"));

return;

}

}

CString ErrorCode;

ErrorCode.Format(_T("备份失败,错误代码为%d"),GetLastError());

AfxMessageBox(ErrorCode);

}

//清空一个OLE记录表TotalRecord--其他形式的可以对照参考:

DelOleRecords()

{

if(m_TmpAdo.Open(_T("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=CMyData\LabResult.mdb")))

{

m_TmpAdo.Execute(_T("delete from TotalRecord"));

}

else

{

AfxMessageBox(m_TmpAdo.GetLastErrorString());

DWORD dwError = m_TmpAdo.GetLastError();

return;

}

m_TmpAdo.Close();

}

补充:

保存记录时使用m_pRs指针,可以使用该类成员函数SetFieldValue之类的,注意的是我给你的那个数据库类记录集指针m_pRs插入新记录时需要先m_pRs.AddNew(),然后执行SetFieldValue才会成功。如果是覆盖插入,在插入数据前需要先调用m_pRs.Edit();并且插入完成后需要m_pRs.UpdateData()一下。

就这么简单!

西柚不是西游

购买sql数据库空间!

我不懂运营

本地装一个Sql Server 不就行了。

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2023-07-19 18:48:151

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夯实的成语有:矮矮实实,踏踏实实,夯雀先飞。夯实的成语有:矮矮实实,夯雀先飞,踏踏实实。2:注音是、ㄏㄤㄕ_。3:拼音是、hāngshí。4:词性是、动词。5:结构是、夯(上下结构)实(上下结构)。夯实的具体解释是什么呢,我们通过以下几个方面为您介绍:一、词语解释【点此查看计划详细内容】夯实hāngshí。(1)捣实。二、网络解释夯实夯实为汉语词语,读音为hāngshí,本意为加固,引申意义为打牢基础,多用于建筑行业。利用重物使其反复自由坠落对地基或填筑土石料进行夯击,以提高其密实度的施工作业。关于夯实的近义词巩固关于夯实的单词tampcompactedtramper关于夯实的词语气夯胸脯心拙口夯关于夯实的造句1、大地,请借我黑土,夯实朋友脚下路;轻风,请借我清凉,让我滋润朋友躁热心。朋友,请借我笑脸,让我祝福你快乐!2、踏踏实实做人,实实在在办事。任何一个双手插在口袋里的人,都爬不上成功的梯子。给人留下一个实在的形象,给自己的成功增添一份夯实的基础,从实际出发,对自己负责。3、据悉,湿地还采用膨润土防水毯作为防渗,湿地边堤及隔堤结构采用砖墙护砌,生态砖护顶,内部园路填土夯实,碎石铺面。4、一块空旷的平地,没有夯实基础,裸露的石块到处都是,一人高的杂草一丛一丛,遍地开花,还有深深的车辙压痕,纵横交错,千疮百痍。5、专家组建议,最好对裂缝进行填埋夯实,以防雨水渗入,引发风化残积层滑动。点此查看更多关于夯实的详细信息
2023-07-19 18:49:341

bootmgr is conmpressed什么意思

翻译过来: “BootMGR引导程序被压缩,请按Ctrl+Alt+Del重新启动” 嘛,出现这个的原因是启动盘被压缩了,导致启动文件无法加载。 修复方法嘛……找个win7的安装盘,从安装盘启动,进启动修复就ok了。 然后成功开机后切记把启动盘的压缩关掉~!
2023-07-19 18:49:441

snow第三人称单数

snow的第三人称单数:snowssnow,名词、及物动词、不及物动词,作名词时意为“雪,积雪;下雪,人名;(英)斯诺”,作及物动词时意为“使纷纷落下;使变白”,作不及物动词时意为“降雪”。snow可以用作名词:snow的基本意思是“雪”,可指“雪花,雪片”,是不可数名词。snow表示“下雪期,积雪,积雪地区”等意思时,一般用复数snows,用作主语时,动词也用复数形式。snow可表示“一场雪”,即一次下雪过程,是可数名词,常用作复数形式。snow用作名词的用法例句:Snow scattered unequally over the mountainside.雪不均匀地散落在山腰上。The compacted snow on the pavement turned to ice.人行道上被踩实的雪已变成了冰。He trudge three hour in the snow to get back home.他在雪中跋涉三个钟点才回到家。snow可以用作动词:snow用作不及物动词时,表示“下雪”,此时不能用表示时间、地点的名词作主语,必须用代词it充当主语。snow用作及物动词时,表示“使…纷纷飘落,使…像雪片似地落下”,可指下雪,也可指类似于下雪的现象。snow在美国非正式语体中还可表示“用花言巧语欺骗、说服或赢得某人的尊敬”。snow用作动词的用法例句:It was snowing heavily.天正在下大雪。I have a hunch that it will snow soon.我有快要下雪的预感。The highway was covered with snow.公路被雪覆盖著。snow用作动词的用法例句:The highway was covered with snow.公路被雪覆盖著。snow用法例句:1、The first snow came a month earlier than usual.第一场雪比往年提早了一个月。2、I"d been a fool letting him snow me with his big ideas.我真蠢,居然被他的胡乱吹嘘给蒙蔽了。3、The snow was light and noiseless as it floated down.雪花轻盈飘落,无声无息。
2023-07-19 18:50:031

Cement Stabilization

Cement is increasingly used as a stabilizing material for soil, particularly for the construction of highways and earth dams. The first controlled soil-cement construction in the United States was carried out near Johnsonville,South Carolina,in 1935. Cement can be used to stabilize sandy and clayey soils. As in the case of lime,cement helps decrease the liquid limit and increase the plasticity index and workability of clayey soils. For clayey soils,cement stabilization is effective when the liquid limit is less than 45 - 50 and the plasticity index is less than about 25.Like lime,cement helps increase the strength of soils,and strength increases with curing time. Table 10. 1 presents some typical values of the unconfined compressive strength of various types of untreated soil and soil-cement mixture made with approximately 10% cement by weight.Table 10. 1 Typical compressive strengths of soils and soil-cement mixturesGranular soils and clayey soils with lowplasticity obviously are most suitable for cement stabilization. Calcium clays are more easily stabilized by the addition of cement,whereas sodium and hydrogen clays,which are expansive in nature,respond better to lime stabilization. For these reasons,proper care should be given in the selection of the stabilizing material.For field compaction,the proper amount of cement can be mixed with soil either at the site or at a mixing plant and then carried to the site. The soil is compacted to the required unit weight with a predetermined amount of water.Similar to lime injection,cement slurry made of Portland Cement and water ( water-cement ratio = 0. 5∶ 5) can be used for pressure grouting of poor soils under foundations of buildings and other structures. Grouting decreases the hydraulic conductivity of soils and increases the strength and the load-bearing capacity. For design of low-frequency machine foundations subjected to vibrating forces,stiffening the foundation soil by grouting and thereby increasing the resonant frequency is sometimes necessary.
2023-07-19 18:50:171

glacier 原听力短文

Glaciers are slowly moving masses of ice that have accumulated on land in areas where moresnowfalls during a year than melts. Snow falls as hexagonal crystals, but once on the ground,snow is soon transformed into a compacted mass of smaller, rounded grains. As the air spacearound them is lessened by compaction and melting, the grains become denser. With furthermelting, refreezing, and increased weight from newer snowfall above, the snow reaches agranular recrystallized stage intermediate between flakes and ice known as firn. With additionaltime, pressure, and refrozen meltwater from above, the small firn granules become larger,interlocked crystals of blue glacial ice. When the ice is thick enough, usually over 30 meters,the weight of the snow and firn will cause the ice crystals toward the bottom to become plasticand to flow outward or downward from the area of snow accumulation.Glaciers are open systems, with snow as the system"s input and meltwater as the system"smain output. The glacial system is governed by two basic climatic variables: precipitation andtemperature. For a glacier to grow or maintain its mass, there must be sufficient snowfall tomatch or exceed the annual loss through melting, evaporation, and calving, which occurswhen the glacier loses solid chunks as icebergs to the sea or to large lakes. If summertemperatures are high for too long, then all the snowfall from the previous winter will melt.Surplus snowfall is essential for a glacier to develop. A surplus allows snow to accumulateand for the pressure of snow accumulated over the years to transform buried snow intoglacial ice with a depth great enough for the ice to flow. Glaciers are sometimes classified bytemperature as faster-flowing temperate glaciers or as slower-flowing polar glaciers.Glaciers are part of Earth"s hydrologic cycle and are second only to the oceans in the totalamount of water contained. About 2 percent of Earth"s water is currently frozen as ice. Twopercent may be a deceiving figure, however, since over 80 percent of the world"s freshwater islocked up as ice in glaciers, with the majority of it in Antarctica. The total amount of ice is evenmore awesome if we estimate the water released upon the hypothetical melting of the world"sglaciers. Sea level would rise about 60 meters. This would change the geography of the planetconsiderably. In contrast, should another ice age occur, sea level would drop drastically. Duringthe last ice age, sea level dropped about 120 meters.When snowfalls on high mountains or in polar regions, it may become part of the glacialsystem. Unlike rain, which returns rapidly to the sea or atmosphere, the snow that becomespart of a glacier is involved in a much more slowly cycling system. Here water may be stored inice form for hundreds or even hundreds of thousands of years before being released again intothe liquid water system as meltwater. In the meantime, however, this ice is not static. Glaciersmove slowly across the land with tremendous energy, carving into even the hardest rockformations and thereby reshaping the landscape as they engulf, push, drag, and finallydeposit rock debris in places far from its original location. As a result, glaciers create a greatvariety of landforms that remain long after the surface is released from its icy covering.Throughout most of Earth"s history, glaciers did not exist, but at the present time about 10percent of Earth"s land surface is covered by glaciers. Present-day glaciers are found inAntarctica, in Greenland, and at high elevations on all the continents except Australia. In therecent past, from about 2.4 million to about 10,000 years ago, nearly a third of Earth"s landarea was periodically covered by ice thousands of meters thick. In the much more distant past,other ice ages have occurred.
2023-07-19 18:50:241

什么叫碾压混凝土RCC工法与RCD工法?

是现行碾压混凝土坝体施工的两种工艺,或叫工法,1、全断面碾压工法(Roller compacted concrete)简称RCC:采用类似土石坝填筑的施工技术和工艺,将干硬性混凝土快速的全面分层振动压实。2、金包银碾压工法(Roller Compacted Dam-Concrete)简称RCD:工法施工工艺简单,连续浇筑,平仓几层,一次碾压。上、下游面和基础结合处用常态混凝土外包,即“金包银”;以解决坝体的防渗,抗冻、防冲.
2023-07-19 18:50:451

渐强的英文,渐强的翻译,怎么用英语翻译渐强,渐强用

growing
2023-07-19 18:50:533

赞美捐献遗体的诗句

 奇迹 【德】约翰内斯·R·贝歇尔  说吧,发生了什么样奇迹?  我可以用你的眼睛看,  你用我的脚步走路,  你没讲的我都懂得,  你的话有如风之吹拂……  你存在,就是我的复苏——  说吧,对我可发生了奇迹?  发生的正是一个奇迹,  通过你我走近了自己。  我的存在就是,你,你在这里。  (发觉没体现谢意……)  另一首曾经记下的(仍然敷衍了些~):  Virtue 美德  -G.Herbert/赫伯特  Sweet day,so cool,so calm,so bright! 甜美的白昼,如此凉爽、安宁、明媚!  The bridal of the earth and sky- 天地间完美的匹配-  The dew shall weep thy fall to-night; 今宵的露珠儿将为你的消逝而落泪;  For thou must die. 因为你必须离去。  Sweet rose,whose hue angry and brave, 美丽的玫瑰,色泽红润艳丽,  Bids the rash gazer wipe his eye, 令匆匆而过的人拭目而视,  Thy root is ever in its grave, 你的根永远扎在坟墓里,  And thou must die. 而你必须消逝。  Sweet spring,美妙的春天,  full of sweet days and roses, 充满了美好的日子和芳香的玫瑰,  A box where sweets compacted lie, 如一支芬芳满溢的盒子,  My music shows ye have your closes, 我的音乐表明你们也有终止,  And all must die, 万物都得消逝。  Only a sweet and virtuous soul, 唯有美好而正直的心灵,  Like season"d timber,never gives; 犹如干燥备用的木料,永不走样;  But though the whole world turn to coal, 纵然整个世界变为灰烬,  Then chiefly lives. 它依然流光溢彩。
2023-07-19 18:51:241

谁有Emily Dickinson success&to make a prairie的诗评?大神们帮帮忙

Success is counted sweetest..." Summary The speaker says that "those who ne"er succeed" place the highest value on success. (They "count" it "sweetest".) To understand the value of a nectar, the speaker says, one must feel "sorest need." She says that the members of the victorious army ("the purple Host / Who took the flag today") are not able to define victory as well as the defeated, dying man who hears from a distance the music of the victors. The three stanzas of this poem take the form of iambic trimeter--with the exception of the first two lines of the second stanza, which add a fourth stress at the end of the line. (Virtually all of Dickinson"s poems are written in an iambic meter that fluctuates fluidly between three and four stresses.) As in most of Dickinson"s poems, the stanzas here rhyme according to an ABCB scheme, so that the second and fourth lines in each stanza constitute the stanza"s only rhyme. Commentary Many of Emily Dickinson"s most famous lyrics take the form of homilies, or short moral sayings, which appear quite simple but that actually describe complicated moral and psychological truths. "Success is counted sweetest" is such a poem; its first two lines express its homiletic point, that "Success is counted sweetest / By those who ne"er succeed" (or, more generally, that people tend to desire things more acutely when they do not have them). The subsequent lines then develop that axiomatic truth by offering a pair of images that exemplify it: the nectar--a symbol of triumph, luxury, "success"--can best be comprehended by someone who "needs" it; the defeated, dying man understands victory more clearly than the victorious army does. The poem exhibits Dickinson"s keen awareness of the complicated truths of human desire (in a later poem on a similar theme, she wrote that "Hunger--was a way / Of Persons outside Windows-- / The Entering--takes away--"), and it shows the beginnings of her terse, compacted style, whereby complicated meanings are compressed into extremely short phrases (e.g., "On whose forbidden ear"). Dickinson"s tiny poem makes a huge statement about the nature of musing, day-dreaming, or as she puts it, "revery." To make a prairie it takes a clover and one bee, One clover, and a bee, And revery. The revery alone will do, If bees are few. Analysis This little poem expresses Dickinson"s continuing love affair with the spiritual level of being. She begins by claiming that to make a physically large item, “a prairie,” all one needs is two small physical items, “a clover and one bee.” Then she qualifies that by saying, “One clover, and a bee / And revery”; then she qualifies that claim further, by saying if you don"t have one of those physical components, “bees,” (and by implication, the clover as well), then you can still make the prairie by revery alone. “Revery” means dream, thought, extended concentration on any subject, or even day-dreaming wherein the mind is allowed to roam free over the landscape of unlimited expansion, but to the speaker in this poem, “revery” is more like meditation which results in a true vision. The speaker"s power of revery demonstrates an advanced achievement, far beyond ordinary day-dreaming or cogitation. Ultimately, this speaker is claiming that without any physical objects at all, the mind of one advanced in the art of revery can produce any object that mind desires. Other Dickinson poems that focus on a similar themes are #632 “The Brain is wider than the sky,” #670 “One need not be a Chamber — to be Haunted,” #674 “The Soul that hath a Guest,” and many others. http://poetry.suite101.com/ blog.cfm/dickinsons_to_make_a_ prairie 参考资料: http://www.sparknotes. com/poetry/dickinson/section1. html满意请采纳
2023-07-19 18:51:331

稠度和流动性的关系(稠度越大是越稀还是越稠啊)搞不懂

这里的稠度概念与通常的正好相反,是稠度测定仪的圆锥体沉入砂浆内的深度。
2023-07-19 18:51:4414

谁有Emily Dickinson success&to make a prairie的诗评!!!

"Success is counted sweetest..." Summary The speaker says that "those who ne"er succeed" place the highest value on success. (They "count" it "sweetest".) To understand the value of a nectar, the speaker says, one must feel "sorest need." She says that the members of the victorious army ("the purple Host / Who took the flag today") are not able to define victory as well as the defeated, dying man who hears from a distance the music of the victors. The three stanzas of this poem take the form of iambic trimeter--with the exception of the first two lines of the second stanza, which add a fourth stress at the end of the line. (Virtually all of Dickinson"s poems are written in an iambic meter that fluctuates fluidly between three and four stresses.) As in most of Dickinson"s poems, the stanzas here rhyme according to an ABCB scheme, so that the second and fourth lines in each stanza constitute the stanza"s only rhyme. Commentary Many of Emily Dickinson"s most famous lyrics take the form of homilies, or short moral sayings, which appear quite simple but that actually describe complicated moral and psychological truths. "Success is counted sweetest" is such a poem; its first two lines express its homiletic point, that "Success is counted sweetest / By those who ne"er succeed" (or, more generally, that people tend to desire things more acutely when they do not have them). The subsequent lines then develop that axiomatic truth by offering a pair of images that exemplify it: the nectar--a symbol of triumph, luxury, "success"--can best be comprehended by someone who "needs" it; the defeated, dying man understands victory more clearly than the victorious army does. The poem exhibits Dickinson"s keen awareness of the complicated truths of human desire (in a later poem on a similar theme, she wrote that "Hunger--was a way / Of Persons outside Windows-- / The Entering--takes away--"), and it shows the beginnings of her terse, compacted style, whereby complicated meanings are compressed into extremely short phrases (e.g., "On whose forbidden ear").Dickinson"s tiny poem makes a huge statement about the nature of musing, day-dreaming, or as she puts it, "revery." To make a prairie it takes a clover and one bee,One clover, and a bee,And revery.The revery alone will do,If bees are few.AnalysisThis little poem expresses Dickinsonu2019s continuing love affair with the spiritual level of being. She begins by claiming that to make a physically large item, “a prairie,” all one needs is two small physical items, “a clover and one bee.”Then she qualifies that by saying, “One clover, and a bee / And revery”; then she qualifies that claim further, by saying if you donu2019t have one of those physical components, “bees,” (and by implication, the clover as well), then you can still make the prairie by revery alone.“Revery” means dream, thought, extended concentration on any subject, or even day-dreaming wherein the mind is allowed to roam free over the landscape of unlimited expansion, but to the speaker in this poem, “revery” is more like meditation which results in a true vision.The speakeru2019s power of revery demonstrates an advanced achievement, far beyond ordinary day-dreaming or cogitation. Ultimately, this speaker is claiming that without any physical objects at all, the mind of one advanced in the art of revery can produce any object that mind desires.Other Dickinson poems that focus on a similar themes are #632 “The Brain is wider than the sky,” #670 “One need not be a Chamber — to be Haunted,” #674 “The Soul that hath a Guest,” and many others.http://poetry.suite101.com/blog.cfm/dickinsons_to_make_a_prairie
2023-07-19 18:52:361

轴的剪应力如何计算?

W是剪切面的面积,
2023-07-19 18:52:474

地球或太空英语诗歌,要初三水平,谁写得好追加50分

Virtue 美德 -G.Herbert/赫伯特 Sweet day,so cool,so calm,so bright! 甜美的白昼,如此凉爽、安宁、明媚! The bridal of the earth and sky- 天地间完美的匹配----- The dew shall weep thy fall to-night; 今宵的露珠儿将为你的消逝而落泪; For thou must die. 因为你必须离去。 Sweet rose,whose hue angry and brave, 美丽的玫瑰,色泽红润艳丽, Bids the rash gazer wipe his eye, 令匆匆而过的人拭目而视, Thy root is ever in its grave, 你的根永远扎在坟墓里, And thou must die. 而你必须消逝。 Sweet spring,full of sweet days and roses, 美妙的春天,充满了美好的日子和芳香的玫瑰, A box where sweets compacted lie, 如一支芬芳满溢的盒子, My music shows ye have your closes, 我的音乐表明你们也有终止, And all must die, 万物都得消逝。 Only a sweet and virtuous soul, 唯有美好而正直的心灵, Like season"d timber,never gives; 犹如干燥备用的木料,永不走样; But though the whole world turn to coal, 纵然整个世界变为灰烬, Then chiefly lives. 它依然流光溢彩。 Think it Over……好好想想…… Today we have higher buildings and wider highways,but shorter temperaments and narrower points of view; 今天我们拥有了更高层的楼宇以及更宽阔的公路,但是我们的性情却更为急躁,眼光也更加狭隘; We spend more,but enjoy less; 我们消耗的更多,享受到的却更少; We have bigger houses,but smaller famillies; 我们的住房更大了,但我们的家庭却更小了; We have more compromises,but less time; 我们妥协更多,时间更少; We have more knowledge,but less judgment; 我们拥有了更多的知识,可判断力却更差了; We have more medicines,but less health; 我们有了更多的药品,但健康状况却更不如意; We have multiplied out possessions,but reduced out values; 我们拥有的财富倍增,但其价值却减少了; We talk much,we love only a little,and we hate too much; 我们说的多了,爱的却少了,我们的仇恨也更多了; We reached the Moon and came back,but we find it troublesome to cross our own street and meet our neighbors; 我们可以往返月球,但却难以迈出一步去亲近我们的左邻右舍; We have conquered the uter space,but not our inner space; 我们可以征服外太空,却征服不了我们的内心; We have highter income,but less morals; 我们的收入增加了,但我们的道德却少了; These are times with more liberty,but less joy; 我们的时代更加自由了,但我们拥有的快乐时光却越来越少; We have much more food,but less nutrition; 我们有了更多的食物,但所能得到的营养却越来越少了; These are the days in which it takes two salaries for each home,but divorces increase; 现在每个家庭都可以有双份收入,但离婚的现象越来越多了; These are times of finer houses,but more broken homes; 现在的住房越来越精致,但我们也有了更多破碎的家庭; That"s why I propose,that as of today; 这就是我为什么要说,让我们从今天开始; You do not keep anything for a special occasion.because every day that you live is a SPECIAL OCCASION. 不要将你的东西为了某一个特别的时刻而预留着,因为你生活的每一天都是那么特别; Search for knowledge,read more ,sit on your porch and admire the view without paying attention to your needs; 寻找更我的知识,多读一些书,坐在你家的前廊里,以赞美的眼光去享受眼前的风景,不要带上任何功利的想法; Spend more time with your family and friends,eat your favorite foods,visit the places you love; 花多点时间和朋友与家人在一起,吃你爱吃的食物,去你想去的地方; Life is a chain of moments of enjoyment;not only about survival; 生活是一串串的快乐时光;我们不仅仅是为了生存而生存; Use your crystal goblets.Do not save your best perfume,and use it every time you feel you want it. 举起你的水晶酒杯吧。不要吝啬洒上你最好的香水,你想用的时候就享用吧! Remove from your vocabulary phrases like"one of these days"or "someday"; 从你的词汇库中移去所谓的“有那么一天”或者“某一天”; Let"s write that letter we thought of writing "one of these days"! 曾打算“有那么一天”去写的信,就在今天吧! Let"s tell our families and friends how much we love them; 告诉家人和朋友,我们是多么地爱他们; Do not delay anything that adds laughter and joy to your life; 不要延迟任何可以给你的生活带来欢笑与快乐的事情; Every day,every hour,and every minute is special; 每一天、每一小时、每一分钟都是那么特别; And you don"t know if it will be your last. 你无从知道这是否最后刻。回答者:dchc - 秀才 三级 9-21 20:31
2023-07-19 18:53:522

以turn开头的短语有哪些

turn on打开turn off关上turn up调高turn down调低
2023-07-19 18:54:012

请帮忙翻译几段话,关于建筑英语的

花园的计划是古典简单、对称、宽敞的作为一个设置雕塑。中央部分是一个cross-axis建立相同的四法院。这些都是平衡南部的沃克和块体的戏剧《北,长方形打开的草地。 轴压于广种石灰石、内衬的菩提树。长,畅通的签字的景色是规模宏大的设计、统一的基础上。“东西方allee终止
2023-07-19 18:54:102

Porosity and Effective Porosity

Total porosity is defined as the part of rock that is void space,expressed as a percentage:w here Vvis the void volume and VTis the total volume. A related parameter is termed the void ratio,designated as e,and stated as:expressed as a fraction,w here Vsis the solid volume. As total volume is the sum of the void and solid volume,the follow ing relationships can be derived:Figure 5. 1 show s some typical kinds of porosity associated w ith various rocks. The term primary porosity is reserved for interstitial porosity ( Figures 5. 1 a - d) ,and the term secondary is used for fracture or solution porosity ( Figures 5. 1 e - f) . Interstitial porosity w as investigated by Graton and Fraser in 1935,w ho demonstrated that its value can range from about 26% to 47% through different arrangements and packing of ideal spheres. In actuality,the porosity of a sedimentary rock w ill depend not only on particle shape and arrangement,but on a host of diagenetic features that have affected the rock since deposition.Figure 5. 1 Relation between texture and porosityPorosity can range from zero or near zero to more than 60% ( Table 5. 1) . The latter value is reflective of recently deposited sediments w hereas the former value is for dense crystalline rocks or highly compacted soft rocks such as shales. In general,for sedimentary materials,the smaller the particle size,the higher the porosity. This is best demonstrated by comparing the porosity of coarse gravels w ith fines,and the total gravel assemblage w ith silts and clays.Table 5. 1 Range in values of porosityAn important distinction is the difference betw een total porosity,w hich does not require pore connections,and effective porosity,w hich is defined as the percentage of interconnected pore space. Many rocks,crystallines in particular,have a high total porosity,most of w hich may be unconnected. Effective porosity implies some connectivity through the solid medium, and is more closely related to permeability than is total porosity. Some data on effective porosity are show n in Table 5. 2. As noted,effective porosity can be over one order of magnitude smaller than total porosity,w ith the greatest difference occurring for fractured rocks.Table 5. 2 Range in values of total porosity and effective porosityHeath in 1982 recognized five types of porosity in dominant w ater-bearing bodies at or near the Earth"s surface in the United States and attempted to map their distribution ( Figure 5. 2) . There are some difficulties w ith this map because of the necessity of mapping a single type of opening in areas w here tw o or more types are present. How ever,this is a useful presentation and one to which we will refer frequently in this chapter. Each pattern on Figure 5. 2 is associated with one or more major water-yielding formations in the United States. Thus,the solution- enlarged openings in carbonate rocks that make up the Florida peninsula are known as the Floridian system; the sands and gravels stretching from New Jersey into Texas are sediments of the Atlantic and Gulf coastal plains; the sand and gravel in the Midwest represents glacial deposits; the sandstones in the northern mid-continent represent several formations,including the Dakota sandstone and the Cambrian-Ordovician system; the sands and gravels in the western part of the nation occupy alluvial basins,whereas the occurrence of these same sediments in central United States represents the remnant of a giant alluvial apron that formed on the eastern slope of the Rocky Mountains; and the basalt in western United States occupies the Columbia River Plateau.Figure 5. 2 Map of conterminous United States showing types of water-bearing openings in the dominant aquifers
2023-07-19 18:54:181

本人高一,下周准备英语课前演讲,继续小短文一篇,最好是关于励志的,谢谢!

噗百度百科吧孩子
2023-07-19 18:54:281

寻六级高频词汇

加我啊我有 word形式的一起努力啊
2023-07-19 18:54:482

计轴的计轴的利弊

不同于轨道电路,计轴不需要安装轨道绝缘,这避免了因为插入绝缘而锯断已焊接好的长轨。这些绝缘部位给钢轨带来薄弱环节,断轨经常发生在这些地点。并且许多轨道电路的故障都是由轨道绝缘引起的。计轴与轨道电路相比,由于不需要钢丝绳并且用较少的电缆,因此安装维修费用低廉。计轴不会遇到诸如轨面污染的问题,例如生锈或肥边(compacted leaf residue)。这些经常影响轨道电路的正确使用。计轴常用在潮湿的隧道,在那里轨道电路是不可靠的。计轴也经常用在钢结构上(钢结构铁路桥,如郑州黄河大桥),这种结构对轨道电路传输有妨害。计轴还经常用在大长区段上,可以节省多个中继点。国外的经验表明,计轴的可用性一般都达到了完成同样功能的轨道电路的5倍以上。这显著的改善了轨道电路应用的可靠性,因为轨道电路失效通常是列车晚点的最主要的原因。计轴还有益于安全,它减少了由于信号系统失效而使用降级模式时带来的室外操作。 计轴容易经常受扰,需要人工复位,有的直接复位,有的预复位。受扰的原因有失电后恢复、电磁干扰、磁头处划过金属物等,岔区的复位如果采用预复位就比较麻烦,但是直接复位又怕出危险。因为掉电等各种原因,轴计数器可能“忘记”一个区段内有多少轴,因此人工操作复位系统是必需的。这引入了不可靠的人为的因素。在国外曾发生被认为因不适当的复位轴计数器造成的事故,尽管在事后的调查中没有被证实。当计轴区段里有车时出现计轴干扰现象时复位,因计计轴处理器复位后已经没有记忆了当车离开区段时计轴磁头检测到了列车离开时的轴数,离开的轴数要和进来的轴数相比较——二者不等,计轴会再度干扰。故障安全计轴仅能提供间断的列车经过固定位置指示。如果计数单元失效或失去连接,列车将没有被检测地进入一个被认为空闲的闭塞区段。但轨道电路能提供连续实时的整个区段的检测,一旦掉电或断线将给列车发送一个安全的信号。轨道电路还允许使用夹子线直接短路电路使轨道电路变为占用,这个方法可以被铁路员工和维修人员使用迅速的报告不安全的情况或区段不能工作。现代计轴装备从轨旁设备通过数据报经由ISDN线传输数据到室内设备,这导致当持续的技术失效或丢失数据报发生社线路区段可以被监视到。区段因此需要复位命令和进一步的交互操作回到工作状态。断轨轨道电路提供附加功能以检测许多但不是所有种类的断轨, 虽然只在限制在交流牵引区段而不是在普通的直流牵引区段。计轴不能提供如此便利的条件。但是,实践表明断轨经常发生在用以隔离相邻区段的绝缘节处。因为单纯的计轴不需要这样的绝缘节,断轨的危险显著降低。转线和调车当车轮直接停在计数机构之上,这是一种临界的状态,计轴有如何正确计数的问题。这反映了在车站或其它的车辆分离和连接的调车区域中计数的不确定性问题。在这些地点手动操纵道岔从正线转侧线,支线或环线轨道用以检测列车从轨道电路段出现和消失的计数器更为重要。电磁制动电磁制动用在高速列车上(最大速度大于160km/h)。有一些体积很大的金属片安装在车辆的转向架上,距钢轨轨几个厘米之上。它们有时被计轴错误地检测到,并认为是其它的车轴。这可能仅发生轨道的一边,因为磁域的弯曲,轨道几何尺寸的缺陷等等,导致信号系统混乱甚至需要复位检测的记忆。现代的AzLM计轴(Alctel)是耐制动系统涡流和磁影响的。该系统的描述说已克服了这个问题,因此计数信息保持稳定,甚至当车辆在检测点的轨面处制动时也如此。
2023-07-19 18:55:011

求冀教版初一英语阅读N篇,越多越好

A Grain of Sand 一粒沙子 William Blake/威廉.布莱克The day is cold, and dark, and dreary; It rains, and the wind is never weary; The vine still clings to the moldering wall, But at every gust the dead leaves fall, And the day is dark and dreary. My life is cold and dark and dreary; It rains and the wind is never weary; My though still cling to the moldering past, But the hopes of youth fall thick in the blast, And the days are dark and dreary. Be still, sad heart! And cease repining; Behind the clouds is the sun still shining; Thy fate is the common fate of all, Into each life some rain must fall, Some days must be dark and dreary. 天冷、阴暗、沉闷; 下着雨,风也刮个不停; 藤还攀附着颓垣残壁, 每来一阵狂风,枯叶附落纷纷, 天真是阴暗而沉闷。 我的生活寒冷、阴郁、沉闷; 下着雨,风也刮个不停; 我的思想还纠缠着消逝的往事, 大风里,我的青春希望相继熄灭, 天真是阴暗而沉闷。 安静吧,忧伤的心!别再悔恨; 乌云后面太阳依然辉煌灿烂; 你命运和大家的一样, 每个人一生都得逢上阴雨, 有些日子必然阴暗而沉闷。 Virtue 美德 G.Herbert/赫伯特 Sweet day, so cool, so calm, so bright! 甜美的白昼,如此凉爽、安宁、明媚! The bridal of the earth and sky- 天地间完美的匹配----- The dew shall weep thy fall to-night; 今宵的露珠儿将为你的消逝而落泪; For thou must die. 因为你必须离去。 Sweet rose, whose hue angry and brave, 美丽的玫瑰,色泽红润艳丽, Bids the rash gazer wipe his eye, 令匆匆而过的人拭目而视, Thy root is ever in its grave, 你的根永远扎在坟墓里, And thou must die. 而你必须消逝。 Sweet spring, full of sweet days and roses, 美妙的春天,充满了美好的日子和芳香的玫瑰, A box where sweets compacted lie, 如一支芬芳满溢的盒子, My music shows ye have your closes, 我的音乐表明你们也有终止, And all must die, 万物都得消逝。 Only a sweet and virtuous soul, 唯有美好而正直的心灵, Like season"s timber, never gives; 犹如干燥备用的木料,永不走样; But though the whole world turn to coal, 纵然整个世界变为灰烬, Then chiefly lives. 它依然流光溢彩。
2023-07-19 18:55:142

植物标本如何长期保存?

植物标本一般有浸制的,还有腊叶标本。 浸制的用福尔马林,硫酸亚铁或者酒精。其中福尔马林的效果最好,准备一个标本瓶加入其中一种液体,将新鲜的植物先用50%的乙醇,70%的乙醇,95%的乙醇和无水乙醇梯度脱水,浸入防腐液中,可以保证标本的新鲜。最后用黄蜡或者凡士林涂抹标本瓶的磨砂口,达到密封的作用。最后在标本瓶上贴上标签即可。 腊叶标本一般不适合花,果和多肉植物的标本制作,因为这类植物的标本即使制作完成也比较容易损坏虫蛀。 准备一些黄草纸,或者报纸,都可以,这个主要是用来吸收水分。 另外需要厚的白卡纸,最好200克以上,用作固定标本。 首先将采集来的植物整理好,保留特征最明显的部分,将多层黄草纸或者报纸在植物的两面铺平放好,上面压上重物,这个过程大概需要一周的时间,期间需要换纸,确保植物的干燥过程顺利。 当压制干燥的植物放入密封的容器内,可以加入氯化苦或者福尔马林来杀菌驱除虫卵。这个过程时间稍微长一些,大约一天可以保证做好的标本存储较长的时间。 最后用棉绳将植物固定在厚卡纸上,贴上标签就可以了。
2023-07-19 18:55:252

韩城地区煤层气井合理动液面高度控制方法探讨

翟雨阳1 胡爱梅1 王芝银2 段品佳2 张冬玲3基金项目:“十一五”国家科技重大专项项目38——煤层气排采工艺及数值模拟技术(2009ZX05038)资助。作者简介:翟雨阳,男,1973年生,博士,主要从事常规油气、煤层气排采及数值模拟研究工作,通讯地址:北京市海淀区地锦路5号中关村环保科技示范园7号楼,E-mail:zhaiyy@nccbm.com.cn(1.中联煤层气国家工程研究中心有限责任公司 北京 1000952.中国石油大学城市油气输配技术北京市重点实验室 北京 1022493.中石油煤层气有限责任公司 北京 100028)摘要:韩城地区煤层属低渗透率煤层气藏,且地质条件复杂,煤岩结构及力学性能差。在煤层气开采初期,井筒内的液柱重力在井底流压中占很大的比例,而井底流压与井周煤岩的应力状态变化规律密切相关。排采降压过程中,过小的动液面高度使煤层处于进一步压密状态,并导致渗透率降低,而过大的动液面高度使井底压力过大进而引起井周岩石产生较大软化破碎区,形成煤粉堵塞渗流通道。因此,研究煤层气动液面高度的合理区间及降低速率对开采过程中有效保持井周应力的合理分布,维持或提高储层渗透率,具有十分重要的意义。本文以韩城示范区为例,利用韩城3#,5#煤层的岩石力学试验,分析了煤岩应力状态与渗透率的关系,通过井周弹塑性应力分析,建立了不同应力状态下保持或提高绝对渗透性的合理动液面高度区间和降低速率。利用所建立的模型对韩城地区WL1,WL2井组进行计算分析,获得了韩城煤层气井开采过程中动液面高度的合理变化区间和排采速率的合理值。本论文研究成果为韩城煤层气井排采强度定量化控制提供了重要的指导意义和借鉴方法。关键词:煤岩 应力 动液面 渗透率 排采速率Discussion on Control Method to Reasonable Height of Dynamic Liquid Level for CBM WellZHAI Yuyang1, HU Aimei1, WANG Zhiyin2, DUAN Pi njia2, ZHANG Dongling3(1.China United Coalbed Methane National Engineering Research Center Co.Ltd.; 2.Beijing KeyLaboratory of Urban Oil and Gas Distribution Technology, China University of Petroleum, Beijing 102249, China; 3.PetroChina CBM Company Limited, Beijing, 100028, China)Abstract: In China, Coal is of low permeability, complex geological conditions, and weak petrographical structure and mechanical performance.In the initial stage of the recovery, the gravity of the liquid column takes a large proportion in bottom-hole pressure (BHP), and the stress state of surrounding rock are closely related with BHP.Thus, in the process of recovery, too small height of the dynamic liquid level makes coal seam be further compacted and leads to permeability reducing; reversely, too much height of dynamic liquid level easily causes BHP too large and induces the surrounding rock breaking in soften, and produces the coal powder and blocks the seepage channels.Therefore, the study on the rational range of dynamic liquid level and the reducing rate have the vital significance to effectively maintain the reasonable distribution of stress state of surrounding rock and increase reservoir permeability.Based on the 3#, 5# coal rock mechanical experiments in Han-cheng, this paper analyses the relationship of the stress state and permeability of coal rock.Through the elastic-plastic stress analysis to the surrounding rock of well, the mathematical model is established, which is about the reasonable range and depres- surization rate of dynamic liquid level to maintain and improve the absolutely permeability.The established models are applied to calculate and analyze the field data of WL1 and WL2 Wells in Han-Cheng.Finally. the reasonable variations of dynamic liquid level are obtained.The researching results provide important instructions and refer- ences to the reasonable recovery control of the coal bed methane in Han-cheng.Keywords: coal rock; stress; dynamic liquid level; permeability; depressurization rate引言煤层气作为非常规能源,对其有效的开采不但可以缓解我国能源短缺的问题,还可以提高煤炭资源的开采效益,并且能够减少对环境(温室效应)的影响。煤层气的有效开采受多种因素的影响,如地质构造特征、煤岩结构、煤阶、渗透率、含气量、解吸吸附特征和开采工艺等[1~5]。因此,煤层气的开采与常规油气开采相比既有相似之处,同时又存在着较大的差异。其中,应力敏感性问题在煤层气工程中表现的尤为显著[6~7]。煤岩储层的渗流能力受孔隙压力变化、煤层气解吸引起的基质收缩作用和滑脱效应的综合影响[8~10]。加载速率和加载方式的不同对煤岩的力学特性和破坏特征有较大的影响,如果加载速率较快,煤岩将呈脆性粉碎性破坏,抗压强度略有提高;相反若加载速率较低,则煤岩抗压强度偏低,延性增大。在煤层气工程实际中,煤岩结构复杂,裂隙(面割理和端割理)十分发育,随着排采的进行煤岩的应力状态将不断发生变化,导致煤岩的裂隙开始发生闭合,然后产生开裂,最终会发生破碎的过程,进而引起储层的渗流系统发生改变,而排采过程中渗透率的变化规律决定着煤层气是否能够高效的开采[1~2]。目前国内外煤层气行业在制定排采工作制度方面主要依靠经验及井筒液面变化来定性确定,这往往导致排采制度不合理,对储层造成伤害,影响开发效益。本文探讨如何通过排采过程中控制煤层气井的合理动液面高度变化规律提高煤层气效益,为煤层气排采强度定量控制提供了科学的理论依据。1 韩城地区煤岩物理力学特性1.1 试验测试煤岩力学特性是反映和研究储层力学行为和应力敏感性的基础数据。利用RW-2000岩石三轴压缩试验机对高径比为2:1的煤岩心试件进行实验,测定了韩城3#,5#和11#煤岩的抗压强度和抗拉强度等参数。其中,抗压强度、弹性模量、泊松比由单轴压缩试验测得;抗拉强度由劈裂试验测得;内摩擦角、粘聚力、残余粘聚力和残余内摩擦角通过三轴压缩强度试验获得,试验结果见表1和表2。表1 韩城煤岩单轴抗压抗拉强度及变形参数表2 韩城煤岩三轴抗压强度试验结果由表1和表2中的实验测试资料可见,韩城煤岩力学特性较差,抗压强度均在10MPa以下。三类煤岩比较而言,3#和5#煤的物理力学特性要比11#煤强,11#煤的残余强度非常低。因此,在煤层气工程中必须注意煤岩力学特性对排采强度控制的影响。1.2 煤岩应力状态影响渗透率变化机理基于对韩城主力产气煤层煤岩(3#,5#和11#煤)进行的室内试验和应力应变全曲线下煤岩应力状态对渗流能力影响关系研究表明,煤岩的绝对渗透率在初始弹性变形阶段是随有效应力的增加而减小,但减小的幅度并不大;当有效应力接近煤岩的峰值强度时,由于原有裂隙的开裂和新裂隙的出现导致渗透率缓慢增加当超过峰值强度后,渗透率迅速增大;但当有效应力接近煤岩的残余强度时,渗透率逐渐趋于稳定。其中,煤岩弹性极限点为原生裂隙开裂、新裂纹开始萌生的临界点。2 合理动液面高度的确定在煤层气开采过程中,随着动液面的降低,储层煤岩应力状态不断发生变化,导致煤岩的结构特征和孔隙率等物理力学特性发生改变,因而影响了储层的渗流能力。在此过程中,储层渗透率的变化规律与煤岩的力学特性和煤岩的应力状态变化规律密切相关。根据煤岩应力状态对绝对渗透率的影响关系,考虑煤层气井井周具有破碎区的弹塑性应力状态,则可以通过对井周围岩进行应力状态变化规律分析,另由煤层气生产不同阶段井周应力分布与井底流压及套压和液柱高度之间的关系,忽略气柱摩擦阻力,推导得出保持储层处于塑性裂隙发育阶段的液柱高度合理区间为中国煤层气技术进展:2011年煤层气学术研讨会论文集则,动液面高度为h′w=H-hw另由工程实际分析可知,井底流压的上限值不超过储层原始压力pe。式中:H为储层埋深;pe,pc,p0分别表示为储层压力,套管压力和原岩平均水平应力;c,φ,cr,φr,St分别表示煤岩的粘聚力,内摩擦角,残余粘聚力,残余摩擦角和抗拉强度;ρg表示液柱重度。因此,要想提高渗透率,应控制合理的动液面高度变化范围,以保持井周应力状态为弹塑性状态,以在井周形成割理或裂隙贯通的流体运移通道,且随着开采过程中塑性区的发展,在井周出现塑性软化区或破碎区,但需防止井周出现过大塑性软化区。合理的动液面高度变化范围与煤岩的力学性质、储层埋深密切相关,尤其是受内摩擦角影响较大。由于储层的软化区受煤粉的影响会使渗透率受到抑制,因此,在煤层气开采过程中需根据储层的力学特性及埋深来合理控制动液面高度,尽量避免软化区大范围产生,以免造成储层伤害而影响煤层气的进一步开采。3 动液面合理降低速率由煤岩的加载速率效应可知,加载速率对煤岩的强度呈正相关影响,同时煤岩脆性亦增强。对于各向异性的煤岩介质,过快的加载速率不利于煤岩中的原始裂隙裂缝的稳定扩展和煤层气的渗透的提高。同理,对于煤层气工程排采过程中的动液面降低速率对井周储层煤岩具有类似的影响机理,如果动液面降低速率过快,将会使储层煤岩有效应力快速增大,最终不合理的动液面降低速率导致煤岩出现脆性破碎并有大量煤粉产生,对储层造成巨大的伤害。所以,煤层气开采不同阶段需控制动液面降低速率在合理值域内。当储层煤岩处于初始弹性应力状态下时,中国煤层气技术进展:2011年煤层气学术研讨会论文集当储层煤岩处于裂隙扩展的塑性阶段,即动液面高度满足(1)式时,中国煤层气技术进展:2011年煤层气学术研讨会论文集式中:h′w表示动液面降低速率;ωcr、ωce为塑性软化阶段和弹性阶段的动液面降压速率上限值,可通过试验和现场数据综合分析确定。4 韩城地区工程应用韩城地区煤层气为多煤层储层联合排采,煤岩力学特性较差,合理的动液面变化规律对煤层气的高效排采具有很大的意义。根据韩城煤岩的试验力学参数和合理动液面高度变化规律的确定方法(见式1~3),对韩城地区WL1和WL2的3#和5#煤联合开采的典型煤层气井排采数据进行了统计计算分析,结果见表3。表3 合理动液面高度降低速率上限值通过拟合分析可得:在开采初期的弹性阶段,3#、5#煤联合开采井的动液面近似合理降低速率上限值h′w(m/d)随储层埋深h(m)的变化规律分别为:h′w≤0.022h~5.188;当井周煤岩处于塑性阶段,3#,5#煤联合开采井的动液面合理降低速率上限值h′w(m/d)随储层埋深h(m)的变化规律为:hw≤0.006h~1.234。开采过程中无论是初始弹性阶段或塑性破坏阶段,动液面降低速率上限值与储层埋深均近似呈线性递增的规律。煤岩力学特性对开采过程中降液速率影响较大,因此对于力学特性较差的储层,需控制好降液速率才能维持较高的排采能力。初始弹性阶段的降液速率比中期塑性阶段的降液速率一般高4~5倍,这也恰好与室内强度实验曲线峰值前后稳定加载的速率值相同。考虑到工程实际中的安全因素,建议取1.2的安全系数。5 结论(1)本文基于煤岩试验揭示了煤层气开采过程中井周煤岩应力状态对渗透率影响的力学机理;储层有效应力随着压降漏斗不断扩展而不断增大,煤岩从原岩区到井壁处,由原始的弹性状态进入塑性状态,在井壁处出现张拉破坏区,此时裂隙开裂积累,日产能达到最大。(2)以韩城地区煤层气工程数据为依托,探讨提出了生产过程中为提高储层的渗流能力,合理动液面高度变化规律的控制范围及降低速率上限值,对煤层气井的合理排采具有借鉴意义。(3)煤层气开采受多种因素的综合影响,还需考虑表皮效应(储层伤害)和压裂效果的影响,有待进一步考虑研究。参考文献[1] 张新民, 张遂安.1991. 中国的煤层甲烷 [M] .西安: 陕西科学技术出版社[2] SCHAFERPS.H V.1992.Aguide to coalbedmethane operations [M] .Chicago: US Gas Research Institute SAULSBERRY JL, SCHAFERPS, SCHRAUFNAGELRA.1996.Aguide to coalbed methane reservoir engineering [M].Chicago: US Gas Research Institute[3] 傅雪海等.2003.多相介质煤层气储层渗透率预测理论与方法 [M] .北京: 中国矿业大学出版社[4] 郝琦.1987.煤的显微孔隙形态特征及其成因探讨 [J] .煤炭学报. (4): 51~54[5] 唐巨鹏,潘一山, 李成全等.2006.有效应力对煤层气解吸渗流影响试验研究 [J] . 岩石力学与工程学报,25 (8): 1563~1568[6] 秦跃平, 王丽,李贝贝,崔丽洁.2010.压缩实验煤岩孔隙率变化规律研究 [J] .矿业工程研究.25 (1): 1~3[7] Jüntgen H.1987.Research for future in situ conversion of coal [J] .Fue, 1, 66: 272[8] Gan H, Nandi S P, Walker P L 1972.Nature of porosity in A-merican coals [J] .Fue, 1 (51): 272~277[10] 苏现波, 陈江峰,孙俊民等.2001.煤层气地质学与探勘开发 [M] .北京:科学出版社[11] 李相臣,康毅力, 罗平亚.2009.应力对煤岩裂缝宽度及渗透率的影响 [J] . 煤田地质与勘察学报, 37(1): 29 ~32[12] Palmer I, Mansoori J.1996.How permeability depends on stress an d pore pressure in coalbeds: a new model . Annual Technical Conference and Exhibition. Denver, Colorado. SPE 36737.557~564
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夯实是什么意思

夯,或打夯,原为建住宅时对地基以人力方式用石头等硬物进行夯实,通常2人以上合作完成工作。现在夯实地基的工作以改为机械夯实,也称打电夯。夯实基础,指采取一些措施,为其打下扎实的基础。
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夯实是什么意思

重型夯锤在重力和液压力的作用下,下落对土壤进行夯实,并在液压缸的作用下实现快速的上下往复动作,在装载机工作装置的牵引下,机动灵活地对不同的位置进行准确、快速的压实,从而满足对夯实作业面积进行单点或连续的压实要求。
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夯实的词性夯实的词性是什么

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2023-07-19 18:56:271

夯实的近义词夯实的近义词是什么

夯实的近义词有:巩固。夯实的近义词有:巩固。拼音是:hāngshí。注音是:ㄏㄤㄕ_。结构是:夯(上下结构)实(上下结构)。词性是:动词。夯实的具体解释是什么呢,我们通过以下几个方面为您介绍:一、词语解释【点此查看计划详细内容】夯实hāngshí。(1)捣实。二、网络解释夯实夯实为汉语词语,读音为hāngshí,本意为加固,引申意义为打牢基础,多用于建筑行业。利用重物使其反复自由坠落对地基或填筑土石料进行夯击,以提高其密实度的施工作业。关于夯实的单词trampertampcompacted关于夯实的成语心拙口夯矮矮实实夯雀先飞踏踏实实关于夯实的词语心拙口夯气夯胸脯关于夯实的造句1、认真学习,增强公道正派的思想意识。善谋实干,夯实公道正派的实践基础。严谨自律,树立公道正派的良好形象。2、大地,请借我黑土,夯实朋友脚下路;轻风,请借我清凉,让我滋润朋友躁热心。朋友,请借我笑脸,让我祝福你快乐!3、一块空旷的平地,没有夯实基础,裸露的石块到处都是,一人高的杂草一丛一丛,遍地开花,还有深深的车辙压痕,纵横交错,千疮百痍。4、民工把土里的矿筛出来后,再把坑填上,回填的土没有经过辗压和夯实,人踩在上面松软松软的。5、据悉,湿地还采用膨润土防水毯作为防渗,湿地边堤及隔堤结构采用砖墙护砌,生态砖护顶,内部园路填土夯实,碎石铺面。点此查看更多关于夯实的详细信息
2023-07-19 18:56:351