多元醇为交联剂制备AA/AMPS耐盐性高吸水性树脂

以丙烯酸(AA)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为单体,环己烷为油相,过硫酸铵为引发剂,采用反相悬浮聚合法制备耐盐性高吸水树脂。研究了单体物料比,交联剂种类及用量,水油比以及不同分散剂种类及配比对吸水树脂吸水率及耐盐率的影响,并通过扫描电子显微镜及傅里叶变换红外光谱对树脂结构进行表征。结果表明:m(AMPS)∶m(AA)为1.0∶10.0,中和度为75%,交联剂甘露醇用量(占单体质量)为6%,水油比为1.0∶3.0,分散剂span60用量(占单体质量)为8.0%,过硫酸铵用量(占单体质量)为0.5%时,制备的耐盐性高吸水树脂的吸水率和吸盐率最高,分别达到1 705,133 m L/g。耐盐性高吸水树脂表面光滑,结构疏松。     

咖啡因分子印迹聚合物微球的悬浮聚合法制备及吸附性能研究

以咖啡因为模板分子,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,采用悬浮聚合法在水溶液中制备印迹聚合物微球.考察功能单体的种类,模板分子与功能单体的比例,模板分子与交联剂比例以及反应时间对印迹聚合物吸附性能的影响,并用SEM观察印迹微球的形貌.结果表明,以α-甲基丙烯酸(MAA)为功能单体制备的印迹聚合物,n(咖啡因)∶n (MAA)∶n (EGDMA)=1∶ 4∶20得到的印迹聚合物微球形貌与吸附性能较好,最大表现结合量为14.0322μmol/g.     

纤维素类高吸水材料的合成与性能研究

本文研究了在K2 S2 O8和 (NH4 ) 2 Ce(NO3) 6不同引发剂作用下丙烯腈单体与甘蔗渣粗纤维纸浆接技聚合反应制备高吸水材料     

初二数学竞赛模拟试卷(二)

一、选择题1.不大于200且只有15个正约数的所有正整数有().(A)1个(B)2个(C)3个(D)4个2.P为等边三角形ABC内部一点,∠APB,∠BPC,∠CPA的大小之比是5∶6∶7,则以PA,PB,PC的长为边的三角形的三个内角的大小之比(从小到大)是().(A)2∶3∶4(B)3∶4∶5(C)4∶5∶6(D)不能确定3.把130件玩具分给幼儿园小朋友,如果不管怎样分,都至少有一位小朋友分得4件或4件以上的玩具,则这个幼儿园最多有小朋友().(A)42个(B)43个(C)44个(D)45个4.已知周长小于15的三角形三边的长都是质数,且其中至少有一边长为3,这样的三角形有().(A)4个(B)5个(C)6个(…     

“勾股定理”测试卷(A卷)

一、选择题(每题4分,共36分)1.在△ABC中,∠C=90°,c=5cm,周长为12cm,则它的面积是().(A)12cm2(B)6cm2(C)8cm2(D)9cm22.如果一个直角三角形两边的长分别为1cm和2cm,那么这个三角形第三边长的平方等于().(A)5cm2(B)3cm2(C)5cm2或3cm2(D)2cm23.一个直角三角形三边之比为3∶4∶5,则这个三角形三边上的高之比为().(A)10∶8∶2(B)5∶4∶3(C)3∶4∶5(D)20∶15∶124.把直角三角形的两条直角边同时扩大到原来的2倍,则其斜边扩大到原来的().(A)2倍(B)2倍(C)3倍(D)4倍5.直角三角形的三边为三个连续的自然数,那么这三个数为().(A)4,5,6(B)2,3,…     

2001年数学中考模拟测试卷(二)参考答案

一、1 Ｂ　 2 Ｃ　 3 Ｂ　 4 Ｄ　 5 Ｄ　 6 Ｂ　 7 Ｃ　 8 Ｄ　 9 Ｃ　 10 Ｃ　 11 Ｂ　 12 Ｃ　 13 Ｄ　 14 Ｃ二、15 2∶5　 16 6　 17 ａ(ａ + 1) (ａ + 2 )　 18 2 2∶ 2 =2∶1或 1∶ 2 =2∶2或 1∶ 2 =2∶2 2等 (填一个即可 )　 19 42 0 4　 2 1 (2ｎ - 1) (2ｎ + 1) =(2ｎ) 2 - 1　 2 2 ＡＢ =ＣＤ或ＡＯ =ＣＯ等 (填一个即可 )　 2 3 2ｃｍ或 7ｃｍ2 4 2 03 ｃｍ三、2 5 (1)错在② .错因 :根据不等式性质 3 ,两边同除以负数 (2 - 5)时 ,不等号应反向 .正确结果应为ｘ <- 45- 9.(2 )错在① .错因 :已知两边及其中一边的对角…     

红车轴草提取物中异黄酮含量的高效液相色谱分析法的研究

建立了一种红车轴草提取物中异黄酮含量的高效液相色谱分析方法。采用日本岛津公司LC - 6AHPLC系统 ,Shim -packVP -DOS柱 (1 5 0mm× 4 6mmID ,5 μm) ,流动相MeOH -CH3 CN -H2 O(体积比 3 7∶1 3∶5 ) ,流速0 9mL·min-1 ,检测波长 2 6 0nm ,柱温 30℃ ,进样量 1 0 μL ;样品制备方法以 1 0mol L-1 HCI甲醇溶液在 85℃条件下水解 1 6h ,HPLC法测定异黄酮的含量 ;该法的RSD为 1 31 % (n =5 ) ,平均回收率为 96 5 %。     

悬浮共聚合法制备激光墨粉的工艺与性能研究

采用悬浮聚合法制备了激光墨粉,以单体配比(n苯乙烯∶n丙烯酸丁酯)6∶1、聚合温度90℃的聚合反应条件所制备的墨粉粒径基本在10μm左右;墨粉整体呈规则的球形;墨粉的软化温度、熔融温度、流动温度分别为60.0℃、62.5℃、70.0℃,符合使用要求.     

2003年重庆市初中数学竞赛

一、选择题 (每小题 5分 ,共 35分 )1.若x 110 0 x 210 0 … x 9910 0 [x 1]=35 6 ,其中 [x]表示不大于x的最大整数 ,则x可取值为 (　　 ) .(A) 3 5 4　　(B) 3 5 5　　(C) 3 4 4　　(D) 3 4 5图 12 .某台球桌为如图 1所示的长方形ABCD ,小球从A沿 4 5°角击出 ,恰好经过 5次碰撞到B处 .则AB∶BC =(　　 ) .(A) 1∶2 (B) 2∶3(C) 2∶5 (D) 3∶53.正整数由小到大排成一列 1,2 ,3,…去掉数列中的完全平方数和完全立方数后 ,不改变顺序 ,组成新数列 .则第 2 0 0个数是 (　　 ) .(A) 2 16 (B) 2 17(C) 2 18(D) 2 194 .已知x y …     

MOAS-a降凝助滤剂的合成、表征及应用性能

MOAS—a降凝助滤剂是以马来酸酐、α—烯烃、丙烯酸酯、苯乙烯(摩尔比为1∶1∶3∶1)为原料,以甲苯为溶剂,以偶氮二异丁腈(用量:4 5g/mol共聚单体)为引发剂,恒温82±2℃聚合6小时,得到四元共聚物(MOAS),再以对甲苯磺酸为催化剂(用量:w=1.5%),用高碳胺[n(酐)∶n(胺)=1∶1 6]进行胺解制得。该剂对东营胜华炼油厂-10#柴油的纯降凝度可达23℃,冷滤点降低可达13℃;对济南炼油厂0#柴油的纯降凝度可达22℃,冷滤点降低可达10℃;对东明0#柴油的纯降凝度可达18℃,冷滤点降低可达9℃;对汤阴5#柴油的纯降凝度可达17℃,冷滤点降低可达7℃。     

β,β′,β″—三氨基三乙基胺合成方法的改进

报告对 β ,β′ ,β″—三氨基三乙基胺合成方法的改进 .改进内容及结果 :改换原料、溶剂和反应条件 ,得到其盐酸盐 ,产率为 84 .0 % (文献为 80 .0 % ) ;自己设计了合理的反应路线 ,得到了终点产物 ,产率为 4 7.2 % .经表征满意 ,效果更佳     

Bilingual and Multilingual Universities in the Republic of Belarus

The Republic of Belarus is a bilingual country, its two principal languages being Belarussian and Russian. Knowledge of other languages is encouraged; indeed, a specialized higher education institution, the Minsk State Linguistic University, has been created to prepare multilingual specialists in various fields. In addition, several non-state higher education institutions have developed bi- and multilingual partnerships with Western higher education institutions.     

体育专科生的压力及应对方式调查

采取问卷调查的方法 ,对河南省部分高校体育专业 1 998～ 2 0 0 1年 2 5 8名专科在校生的压力源及应对方式进行了调查 .结果表明 ,2 5 8名体育专科生的前 1 0位压力源为准备及参加考试、毕业分配等项 .常采用的应对方式为 :接受现实 ,心胸开阔 ;独自探路、顺其自然 ;遇友谈心 ,重塑自我等 1 0项 .根据调查结果 ,提出了正确引导学生勇敢面对和恰当应对压力的措施     

Learning Professional Ways of Being: Ambiguities of becoming

The purpose of professional education programs is to prepare aspiring professionals for the challenges of practice within a particular profession. These programs typically seek to ensure the acquisition of necessary knowledge and skills, as well as providing opportunities for their application. While not denying the importance of knowledge and skills, this paper reconfigures professional education as a process of becoming. Learning to become a professional involves not only what we know and can do, but also who we are (becoming). It involves integration of knowing, acting, and being in the form of professional ways of being that unfold over time. When a professional education program focuses on the acquisition and application of knowledge and skills, it falls short of facilitating their integration into professional ways of being. In addition, through such a focus on epistemology (or theory of knowing), ontology (or theory of being) is overlooked. This paper explores what it means to develop professional ways of being where the focus is becoming, not simply knowing as an end in itself.     

First-Grade Students and Their Parents

Recent changes to the budgetary basis of schools in Russia has received a mixed response from parents, with a variety of views on whether the quality of education is being improved. Reductions in state support for preschool education raises questions about the ability of less affluent parents to prepare their children for first grade.     

Philosophy of Science and School Science

The purpose of professional education programs is to prepare aspiring professionals for the challenges of practice within a particular profession. These programs typically seek to ensure the acquisition of necessary knowledge and skills, as well as providing opportunities for their application. While not denying the importance of knowledge and skills, this paper reconfigures professional education as a process of becoming. Learning to become a professional involves not only what we know and can do, but also who we are (becoming). It involves integration of knowing, acting, and being in the form of professional ways of being that unfold over time. When a professional education program focuses on the acquisition and application of knowledge and skills, it falls short of facilitating their integration into professional ways of being. In addition, through such a focus on epistemology (or theory of knowing), ontology (or theory of being) is overlooked. This paper explores what it means to develop professional ways of being where the focus is becoming, not simply knowing as an end in itself.     

料浆法制备铜酞菁

通过对料浆法合成铜酞菁(CuPc)的一系列研究，证明了料浆法解决了传统生产CuPc的溶剂法和固相法长期存在的一些问题。使CuPc的制备可以在工艺简单、无结块、无粘连、生产周期短与反应易控制的条件下，得到较高收率和质量的产品。     

Evaluating postgraduate preparation in the South African context

Little work is being undertaken in South Africa to systematically and intentionally prepare undergraduate students to pursue postgraduate studies. This is concerning given the shortage of postgraduate students and the small scale of postgraduate studies. The few programmes and endeavours that exist to prepare students for postgraduate studies are not necessarily evaluated to assess their achievements and shortcomings. This paper provides an evaluation of an academic year-long postgraduate preparation programme, and is specifically concerned with examining subsequent postgraduate enrolment and improvement of participants’ marks. The study draws on both quantitative and qualitative data. The findings indicate that the majority of programme participants proceeded to subsequently enrol in postgraduate studies immediately after completing the programme and that the programme played a role in the pursuit of postgraduate studies. However, the findings also indicate that overall participants’ marks did not improve after participating in the programme. The study brings to light that, while some achievements are possible, the limits of the programme must also be acknowledged.     

试论陈炽的国防思想

陈炽，早期维新思想家，他的国防思想形成于19世纪90年代。自强自立的爱国精神是其国防思想形成的基础。四维说是其边防思想的主要内容。海防思想上他主张控制南洋，筹划东海防务，具有了初步的海权意识。他的国防思想贯穿着“勤远略”，“先富而后强”，“国防高于生存”等新的国防价值观。     

Bringing effective instructional practice to scale in American schools: Lessons from the Long Beach Unified School District

Workforce and societal needs have changed significantly over the past few decades while educational approaches have remained largely the same over the past 50 years. Walk into any random classroom in the United States and you will likely see instruction being delivered to students in straight rows by teachers through lecture style. It is possible to find classrooms that utilize technology and cross-disciplinary projects to explore real-world problems, however, those are scarce and in high demand. If we are serious about transforming instruction to better prepare our students for a global society, we need to do it beyond one classroom, school, or zip code, Long Beach Unified school district provides an uncommon example of an education system that has successfully improved instruction across schools by improving the overall district system. This chapter details how the district created a strong coherent system by connecting the critical elements necessary to scale and sustain high quality instruction for all students, and ultimately, better prepare them for the changing demands of our country’s global economy.