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解答有关溶解度图象类题目要把握溶解度的概念,其次要明确溶解度曲线的意义:(1)利用溶解度曲线,可求出物质在不同温度下的溶解度;(2)比较同温下不同物质的溶解度大小;(3)根据溶解度曲线倾斜度大小,可以确定物质的溶解度受温度的影响程度,并判断析晶方法;(4)可判断物质是否易溶、可溶、微溶、难溶;(5)两条溶解度曲线相交,表示该交点温度下这两种物质的溶解度相等,同时也表示两物质在该温度下的饱和溶液的溶质质量分数相等;(6)曲线上的点表示溶液是饱和溶液,曲线以下的区域表示不饱和溶液区,曲线以上的区域表示配制的溶液为饱和溶液,但溶质有剩余; 例1 某同学根据如图所示溶解度曲线获得以下信息,其中正确的是(). 相似文献
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关于(6/7)<()<(7/8)的解,《云南教育》84年第五期和85年第二期刊登了几种解法。本文谈谈(6/7)<()<(7/8)的所有解,即通解。为了探讨这道题的所有解,可以在数轴上画出表示(6/7)和(7/8)的两点。从图上可看出,凡在(6/7)和)(7/8)这两点之间所有的点表示的数 相似文献
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英语的独立主格结构(nominative absoluteconstruction)的句法功能是在句中作状语,可以表示谓语动词的动作时间、原因、伴随情况和方式等。它包括六种形式:(1)名词或代词+介词;(2)名词或代词+不定式;(3)名词或代词+介词短语;(4)名词或代词+形容词;(5)名词或代词+名词;(6)名词或代词+副词。在这些结构中,前面的名词或代词是后面部分的逻辑主语。英、汉两种语言虽不同语系,汉语的复句不一定能够译成英语的复句,但在多数情况下可以用英语的独立主格结构处理,这样翻译出来的句子简洁,语言紧凑、流畅,一目了然。下面试就汉语一些有关的联合复句和… 相似文献
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中学古文虚字众多,要求掌握的亦有不少。在复习备考中,通过系统整理,依其用法,编成顺口溜,帮助记忆理解大有好处。现以“之”字为例,简要说明如下: 顺口溜:“之”代它称人物事, 情况复杂须细致;(1) 有时活用代自己;(2) 有时用作指代词;(3) “之”当结构助词的;(4) 有时表示宾前置;(5) 补助音节表语气;(6) 主谓之间也用“之”(7) 以上三种不翻译, 相似文献
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1.李琦的34位同学中,有12位喜食冰激凌,有8位喜食果冻,有6位喜食薯条,其余的同学中有一半喜食牛肉干,另一半喜食果脯.若用扇形统计图表示这些数据,则表示喜食牛肉干者应该占的角度是().(A)10°(B)20°(C)30°(D)50°(E)42°2.妈妈在超市准备挑选1种肉类、2种不同蔬菜以及1种点心.若不计较食物的挑选次序,则在下面的菜单中有不同的选择方法()种.○肉类:牛肉、鸡肉、猪肉;○蔬菜:青豆、玉米、马铃薯、番茄;○点心:巧克力糖、蛋糕、夹心面包、冰激凌.(A)4(B)24(C)72(D)80(E)1443.如图1,设A,B,C3点为一个等边三角形的3个顶点,而M,N,P是三… 相似文献
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《中学数学教学参考》2001,(3)
代数部分数与式一、选择题1 下列五个命题 :( 1)零是最小的实数 ;( 2 )数轴上所有的点都表示实数 ;( 3)无理数就是带根号的数 ;( 4 ) - 12 7的立方根是± 13 ;( 5)一个实数的平方根有两个 ,它们互为相反数 .其中正确命题的个数为 ( ) .Ａ .1 Ｂ .2 Ｃ .3 Ｄ .42 实施西部大开发战略是党中央面向 2 1世纪的重大决策 .西部地区约占我国国土面积的 23 ,我国国土面积约 960万平方千米 .若用科学计数法表示 ,则我国西部地区的面积为 ( ) .Ａ .64 0× 10 4平方千米 Ｂ .64× 10 5 平方千米Ｃ .6 4× 10 6 平方千米Ｄ .6 4× … 相似文献
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《数学教学通讯》1984,(4)
(1954年2月25日,星期二,上午9,00~10,30) 100022522一2482等于(A)62500;(B)1000;(D)25。;(E)专·(C)500: 一~__1~~止~。,’Z。右匕劣、珍刁们甘一二二百p月、2习禅令,只jJ 云、二一工 夕 l甘一— 劣等于 5.满足n20o<5300的最大整数n是 (A)8;(B)9:(C)10:(D)11; (E)12.() 6.在某学校里,男生是女生的三倍,而女生是教师的九倍,男生、女生和教师的数目分别用字母b,夕,t表示,则男生、女生和教师的总数可表示为(A)1;(B)奋;‘c,圣;(D)普一签;(E)X。一扁(A)3lb;(B)纂“;(c),3。;(D)知;‘E,纂‘.() 3.设戈是满足下列条件的最小正数:大于1.没… 相似文献
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Islam MR Khandoker MA Afroz S Rahman MG Khan RI 《Journal of Zhejiang University. Science. B》2007,8(7):465-469
Goat ovaries were collected from the slaughterhouse and categorized as right, left, corpus luteum （CL）-present and -absent group and evaluated on the basis of weight （g）, length （cm）, width （cm）, number of follicles, follicles aspirated and number and state ofcumulus-oocyte-complexes （COCs）. Comparatively higher weight [（0.66±0.02） vs （0.64±0.02） g], length [（1.17±0.02） vs （1.1 ±0.02） cm] and width [（0.77±0.02） vs （0.74±0.02） cm] were found in right ovaries than those of left. On the other hand significantly （P〈0.05） higher weight [（0.71±0.03） vs （0.64±0.01） g] and width [（0.76±0.03） vs （0.75±0.01） cm] were found in CL-present group than those of CL-absent group of ovaries. The left ovaries contained comparatively higher number of normal COCs [（1.06±0.09） per ovary] than fight ovaries [（1.03±0.10） per ovary] and the similar trend was found in total number of follicles [（4.51±0.25） vs （4.30±0.23） per ovary] and follicles aspirated [（2.55±0.14） vs （2.52±0.12） per ovary]. But the total COCs per ovary was almost similar in both ovaries [right and left： （1.85±0.12） and （1.85±0.11） per ovary, respectively]. Higher number of total COCs [（1.87±0.09） vs （1.76±0.16） per ovary], total number of follicles [（4.45±0.19） vs （4.16±0.37） per ovary], follicles aspirated [（2.55±0.10） vs （2.48±0.21） per ovary] and normal COCs [（1.12±0.07） vs （0.76±0.14） per ovary] were found in CL-absent group than those of CL-present group of ovaries. 相似文献
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教育全球化发展的新动向概述 总被引：1，自引：0，他引：1
20世纪中后期以来,教育全球化发展的新动向主要表现在:教育的国际交流与合作日益增加;教育的国际交流朝着教育贸易方向发展;教育国际交流的主体改变了;世界留学生的规模急剧扩大;教育的国际化使各国教育课程发生了显著变化;教育规模的迅速扩大;教育超越学校教育的范畴;教育向社会的全方位渗透等。 相似文献
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To assess the influence of cyclosporin A (CsA) and tacrolimus (FK506) on mycophenolic acid (MPA) and correlation analysis
of the pharmacokinetic parameters and patient characteristics, clinical outcome in Chinese kidney transplant recipients, the
pharmacokinetics of 1000 mg mycophenolate mofetil (MMF) twice daily was measured by high-performance liquid chromatography
(HPLC). PKS (Pharmaceutical Kinctics Software) 1.0.2 software package was used for the calculation of pharmacokinetic parameters.
The meanC
max,t
max, and AUC(0–12) were (21.88±10.52) μg/ml, (1.20±0.95) h, and (52.546±13.215) μg·h/ml, respectively. The level of AUC(0–12) in the FK506 group was significantly higher than that in the CsA group. MPA appeared not to be affected by renal function.
MPA AUC(0–12) showed statistically significant difference according to the patient's gender.
Project (No. 20040462) supported by the Foundation of Education Bureau of Zhejiang Province, China 相似文献
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本文从十个方面论述了中国古代文学教材中现有的问题，并对某些问题提出了自己的一些设想。这十个问题是：1、中国古代文学的名实不符；2、对古代文化的评价落后；3、把文学作品当作信史看待；4、情理分析的尺度欠妥；5、教材的结构杂乱；6、成就与特点混淆；7、对文学自身规律认识不够；8、对社会人生重视不够；9、教材的观点太死；10、文学史与作品选不配套。 相似文献
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Rowland Monday Ojo Kayode Anthony Jide Afolayan 《Journal of Zhejiang University. Science. B》2015,16(8):680-689
Renewed interest in natural materials as food flavors and preservatives has led to the search for suitable essential oils. Moringa oleifera seed essential oil was extracted by solvent-free microwave and hydrodistillation. This study assessed its chemical constituents. Cytotoxicity of the oils was investigated using hatchability and lethality tests on brine shrimps. A total of 16 and 26 compounds were isolated from the hydrodistillation extraction (HDE) and solvent-free microwave extraction (SME) oils, respectively, which accounted for 97.515% and 97.816% of total identifiable constituents, respectively. At 24 h when the most eggs had hatched, values of the SME (56.7%) and HDE (60.0%) oils were significantly different (P<0.05) from those of sea water (63.3%) and chloramphenicol (15.0%). Larva lethality was different significantly (P<0.05) between HDE and SME oils at different concentrations and incubation periods. The median lethal concentration (LC50) of the oils was >1000 mg/ml recommended as an index for non-toxicity, which gives the oil advantage over some antioxidant, antimicrobial, therapeutic, and preservative chemicals. 相似文献
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高校图书馆读者需求论 总被引：1，自引：0，他引：1
叶建国 《上海师范大学学报(哲学社会科学版)》2003,32(3):106-109
研究和探讨读者需求,是为了更好地为读者服务,提升高校图书馆文献的利用率,文章分别对学生和教师的阅读需求特征作了分析。学生阅读需求特征为:1.阶段性;2.集中性;3.广泛性。教师的阅读需求特征为:1.全面系统;2.专深具体;3.新颖及时。 相似文献
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浅论新时期高校辅导员的职业素质要求 总被引：8，自引：0，他引：8
面对新的形势和任务对高校德育工作提出的挑战，高校辅导员必须具备相应的职业素质，即：树立符合创新人才培养的德育观，坚定理想信念和提高政治理论功底，具有正确的职业价值观念和崇高的敬业奉献精神，具备良好的职业心理素质，掌握系统的心理学知识与能力，提高人素养和化底蕴等。 相似文献
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The coal tar was qualitative and quantitative anMyzed by gas chromatography （GC） method. 74 components were identified exactly by gas chromatographY-mass spectrometry （GC-MS）. 31 components （37%） were quantitatively analyzed by gas chromatography-flame ionization detector （GC-FID）. The linearity, accuracy, precision, limit of detection （LOD） and limit of quantitative （LOQ） determination were inspected. The scope of quantitative analysis by CC was discussed. The experimental results of thermogravimetric analysis （TGA） proved that GC quantitative analysis of the coal tar was reliable. 相似文献
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Studies on characteristics of nanostructure of N-TiO2 thin films and photo-bactericidal action 总被引：1，自引：0，他引：1
Pseudomonas aeruginosa strain （AS 1.50） and Bacillus subtilis strain （AS 1.439） from Ming lake were decomposed by photocatalytic nanostructure N-TiO2 thin films in a photo-reactor under UV irradiation. The different thickness nanostructure N-TiO2 thin films coated on mesh grid were prepared by sol-gel method and immobilized at 500 ℃ （films A） or 350 ℃ （films B） for 1 h in a muffle furnace. The results showed that N-TiO2 thin film B （8.18 nm thickness, 2.760 nm height and 25.15 nm diameter） has more uniform granular nanostructure and thinner flat texture than N-TiO2 thin film A （12.17 nm thickness, 3.578 nm height and 27.50 nm diameter）. The bactericidal action of N-TiO2 thin film A and film B for Pseudomonas aeruginosa strain （AS 1.50） and Bacillus subtilis varniger strain （AS1.439） were investigated in this work. More than 95% of photocatalytic bactericidal efficiency for Pseudomonas aeruginosa strain （AS 1.50） and 75% for Bacillus subtilis strain （AS 1.439） were achieved by using N-TiO2 thin films-B for 70-80 rain of irradiation during the photo-bactericidal experimental process. The results indicated that the photo-induced bactericidal efficiency of N-TiO2 thin films probably depended on the characteristics of the films. 相似文献
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Instructional Design of Web-based Simulations for Learners with Different Levels of Spatial Ability 总被引：1，自引：0，他引：1
Hyunjeong Lee 《Instructional Science》2007,35(6):467-479
This study, the purpose of which is to determine an efficient instructional design for different levels of spatial abilities,
investigates: (1) the main effects of visual treatments in simulation environments on comprehension and the transfer of chemistry
knowledge and (2) the interaction effects of the visual treatments and the learners’ spatial abilities. Two hundred and fifty-seven
middle school students were randomly assigned to two experimental conditions. The results indicated: (1) a significant main
effect of the treatment condition for both comprehension (p < 0.001) and transfer (p < 0.005) tests, where the treatment group performed better than the control group and (2) a significant interaction effect
(p < 0.05) between the instructional treatment conditions and level of spatial ability for the comprehension test: Low spatial
ability learners performed better in the treatment group than in the control group, whereas high spatial ability learners
performed similarly regardless of the instructional conditions. 相似文献