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基于一种新型含菲并咪唑基二胺单体的聚酰亚胺的合成与性能

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化工新型材料 2022年第4期50卷 66-71,76页

作者：孔德禄郭晓霞 Pradip Kumar Tapaswi Chang-Sik ha 张崇印房建华上海交通大学化学化工学院上海200240 Department of Polymer Science and Engineering School of Chemical EngineeringPusan National UniversityBusan 46241South Korea narasinha Dutt College University of CalcuttaKolkata 711101India 上海航天设备制造总厂有限公司上海航天特种环境高分子功能材料工程技术研究中心上海200245

通过三步反应合成了一种新型具有高度扭曲构型的芳香二胺单体1,2-双(4-(4-氨基-2-三氟甲基苯氧基)苯基)-菲并[9,10-d]咪唑(PIPOTFA),将它与四种商业化二酐4,4'-六氟异丙基邻苯二甲酸酐(6FDA)、3,3',4,4'-二苯醚四甲酸二酐(ODPA)、3,3',4... 详细信息

通过三步反应合成了一种新型具有高度扭曲构型的芳香二胺单体1,2-双(4-(4-氨基-2-三氟甲基苯氧基)苯基)-菲并[9,10-d]咪唑(PIPOTFA),将它与四种商业化二酐4,4'-六氟异丙基邻苯二甲酸酐(6FDA)、3,3',4,4'-二苯醚四甲酸二酐(ODPA)、3,3',4,4'-联苯四甲酸二酐(bPDA)和3,3',4,4'-二苯甲酮四甲酸二酐(bTDA)通过高温一步法聚合制得了四种聚酰亚胺均聚物。这些聚酰亚胺在n-甲基吡咯烷酮(nMP)、n,n-二甲基乙酰胺(DMAc)和n,n-二甲基甲酰胺(DMF)等非质子极性溶剂中均具有良好的溶解性。热分析测试结果表明,这些聚酰亚胺具有优异的热稳定性,其玻璃化转变温度在265~290℃之间,氮气气氛下5%和10%热失重温度分别为517~561℃和547~587℃,700℃时的残炭率为60%~70%。这些聚酰亚胺薄膜呈淡黄色,在450nm处的透过率为11%~68%,截止波长为375~383nm。

关键词：聚酰亚胺热稳定性溶解性

Genomic Characteristics of SARS-CoV,MERS-CoV and 2019-nCoV

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Chinese Journal of biomedical Engineering(English Edition) 2021年第1期30卷 30-39页

作者： LI Tong YU Xing CHEn Meng-xiang LV Yuan zha Wen-ting Medical College of Hunan normal University Key Laboratory of Molecular Epidemiology of Hunan ProvinceSchool of MedicineHunan Normal UniversityChangsha 410081China

In December 2019, Wuhan, the capital of Hubei Province in China,reported a series of unexplained cases of pneumonia, which has been confirmed to be an acute infectious respiratory disease caused by novel Corona Virus 2019(2019-nCoV)infection. The World Health Organization(WHO) named this pneumonia Corona Virus Disease 2019(COVID-19). The 21 st century had witnessed the spread of two previously unrecognized coronaviruses around the world with high pathogenicity before, namely severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome coronavirus(MERS-CoV) respectively. At present, 2019-nCoV ’s genome has been sequenced by researchers all over the world represented by China. based on the systematic review and analysis of the genomic sequence characteristics of three highly pathogenic coronaviruses, this paper expounds the basic characteristics of the genomes of SARS-CoV, MERS-CoV and 2019-nCoV,which all belong to β-coronaviruses, the functionally important ORFs, ORF1 a, ORF1 b and major structural proteins including the spike(S), membrane(M) and envelop(E) and nucleiccapsid(n) proteins have no significant difference with each other. However, as the majority of genetic variations being seen at the n-terminal part of S protein, 2019-nCoV aligned best with the bat SARS-like virus bat-SL-CoVZX45. And Structure analysis of the spike(S) protein of2019-nCoV showed that it’s S protein only binds weakly to the Angiotensin Converting Enzyme2(ACE2) receptor on human cells whereas the human SARS-Cov exhibits high affinity to the ACE receptor and MERS-Cov does not need ACE2 to infect human cells,its receptor on human cells is DPP4. In the future, we hope to provide new ideas for the prevention and treatment of coronavirus by strengthening the research of coronavirus S protein and ACE2 receptor, and continuous surveillance and genomic characterization of coronaviruses from bats are necessary due to potential risks of human infection induced by a ge

关键词： 2019-nCoV SARS-CoV MERS-CoV COVID-19 genomic characteristic

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三氯乙烯副产HCl气体净化项目运行总结

中国氯碱 2018年第3期 16-19页

作者：王立民韩强张超张玲玲滨化集团股份有限公司山东滨州256600

介绍了净化装置生产中的配套工艺、设备及控制系统的应用,分析了生产运行中存在的问题,并提出了解决方案。

关键词：净化副产氯化氢装置运行

Favorable surgical treatment outcomes for chronic constipation with features of colonic pseudo-obstruction

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World Journal of Gastroenterology 2012年第32期18卷 4441-4446页

作者： Eon Chul han Heung-Kwon Oh Heon-Kyun ha Eun Kyung Choe Sang Hui Moon Seung-bum Ryoo Kyu Joo Park Department of Surgery Seoul National University College of MedicineSeoul 110-744South Korea Seoul national University Hospital Gangnam Center Seoul 110-744South Korea

AIM:To determine long-term outcomes of surgical treatments for patients with constipation and features of colonic ***:Consecutive 42 patients who underwent surgery for chronic constipation within the last 13 years were prospectively *** identified a subgroup with colonic pseudo-obstruction(CPO) features,with dilatation of the colon proximal to the narrowed transitional zone,in contrast to typical slowtransit constipation(STC),without any dilated colonic *** outcomes of surgical treatments for chronic constipation with features of CPO were analyzed and compared with outcomes for ***:Of the 42 patients who underwent surgery for constipation,33 patients had CPO with dilatation of the colon proximal to the narrowed transitional *** were 16 males and 17 females with a mean age of 51.2 ± 16.1 *** had symptoms of chronic intestinal obstruction,including abdominal distension,pain,nausea,or vomiting,and the mean duration of symptoms was 67 mo(range:6-252 mo).Preoperative defecation frequency was 1.5 ± 0.6 times/wk(range:1-2 times/wk).Thirty-two patients underwent total colectomy,and one patient underwent diverting transverse *** was no surgery-related *** histologic examination showed hypoganglionosis or agangliosis in 23 patients and hypoganglionosis combined with visceral neuropathy or myopathy in 10 *** contrast,histology of STC group revealed intestinal neuronal dysplasia type b(n = 6) and visceral myopathy(n = 3).Early postoperative complications developed in six patients with CPO;wound infection(n = 3),paralytic ileus(n = 2),and intraabdominal abscess(n = 1).Defecation frequencies 3 mo after surgery improved to 4.2 ± 3.2 times/d(range:1-15 times/d).Long-term follow-up(median:39.7 mo) was available in 32 patients;all patients had improvements in constipation symptoms,but two patients needed intermittent medication for management of *** 32 patients had distinct

关键词：手术治疗肠梗阻结肠便秘慢性假性平均年龄 CPO

2015年陕西中医药大学在职教职工脂代谢现状

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职业与健康 2018年第6期34卷 772-775页

作者：张志刚韩梅张强齐宝宁苏衍进陕西中医药大学公共卫生学院陕西咸阳712046 青岛市妇女儿童医院信息统计科山东青岛266034 陕西中医药大学附属医院健康管理中心陕西咸阳712000 陕西中医药大学附属医院内分泌科陕西咸阳712046

目的了解2015年陕西中医药大学在职教职工脂代谢现状,为制定预防控制措施提供参考。方法选择陕西中医药大学参加2015年健康检查的715名在职教职工为研究对象,进行体格测量和血脂检测。结果 715名教职工总胆固醇(TC)、甘油三酯(TG)、高... 详细信息

目的了解2015年陕西中医药大学在职教职工脂代谢现状,为制定预防控制措施提供参考。方法选择陕西中医药大学参加2015年健康检查的715名在职教职工为研究对象,进行体格测量和血脂检测。结果 715名教职工总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)和低密度脂蛋白(LDL-C)水平分别为4.41、1.18、1.32和2.62 mmol/L,不同性别、年龄教职工TC、TG、HDL-C和LDL-C水平间差异有统计学意义(PbMI)教职工HDL-C水平差异有统计学意义(P<0.05)。脂代谢异常总检出率为27.55%,其中高TC血症、高TG血症、混合型高脂血症和低HDL-C血症检出率分别为1.82%、11.05%、1.96%和12.73%;脂代谢异常及其临床类型在不同性别间差异有统计学意义(P<0.05)。结论该校在职教职工脂代谢异常检出率较高,脂代谢异常以低HDL-C血症和高TG血症为主,亟需进行干预控制。

关键词：教职工脂代谢血脂异常

Quantitative and qualitative changes of humus in whole soils and their particle size fractions as influenced by different levels of compost application

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Agricultural Sciences 2011年第1期2卷 1-8页

作者： Thu ha nguyen haruo Shindo 不详

Effect of long-term application (ca. 30 years) of compost at different levels on humus composi-tion of whole soils and their particle size frac-tions in a field subjected mainly to double cropping (barley and paddy rice) was investi-gated. Soil samples were collected from three plots of different types of management: (a) F plot, only chemical fertilizers containing n, P and K were applied;(b) F+LC plot, both chemi-cal fertilizers and a low level of compost were applied;(c) F+HC plot, both chemical fertilizers and a high level of compost were applied (the amount of compost applied in the F+HC plot was three times larger than that applied in the F+LC plot). Each soil sample was divided into coarse sand- (CSA), medium sand-(MSA) and fine sand-(FSA) sized aggregate, silt-sized ag-gregate (SIA) and clay-sized aggregate (CLA) fractions by wet-sieving and sedimentation. In addition, the CSA and MSA fractions were sub-divided into “mineral particles” (MP) and “de-cayed plants” (DP) by a density fractionation. Humus composition was influenced depending upon the level of compost applied. The applica-tion induced an increase in the amounts of total humus (TH), humic acid (ha) and fulvic acid (FA) in the whole soil and many size fractions, par-ticularly, SIA fraction. The increase was re-markable in the F+HC plot. In the CSA and MSA fractions, the amounts of TH, ha and FA were much larger in the CSA- and MSA-DP fractions than in the CSA- and MSA-MP fractions. The amounts of TH, ha and FA in the SIA fraction were larger than those in the CLA fraction for the F+HC and F+LC plots, and the reverse was true for the F plot. On the other hand, the de-grees of humification of humic acids in whole soils and many size fractions, particularly SIA fraction, decreased by compost application. The decrease was markedly in the F+HC plot. These findings suggest that the SIA fraction play an important role in the quantitative and qualitative changes of humus, including ha and FA, as in-fluenced

关键词： Paddy and Upland Fields Straw-Cow Dung Compost Humic and Fulvic Acids Humification

Effects of different levels of compost application on amounts and distribution of organic nitrogen forms in soil particle size fractions subjected mainly to double cropping

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Agricultural Sciences 2011年第3期2卷 213-219页

作者： Thu ha nguyen haruo Shindo Faculty of Agriculture Yamaguchi University Yamaguchi Japan

Effects of different levels of compost application on the amounts and percentage distribution of organic n forms in whole soils and particle size fractions were investigated. Soil samples were collected from three plots: (a) F, only chemical fertilizers;(b) F+LC, chemical fertilizers plus low level of compost;(c) F+HC, chemical fertilizers plus high level of compost. Each soil sample was divided into five fractions: coarse sand-sized aggregate (CSA), medium sand-sized aggregate (MSA), fine sand-sized aggregate (FSA), silt-sized aggregate (SIA) and clay-sized aggregate (CLA) fractions. The sand fractions were subdivided into decayed plants (DP) and mineral particles (MP). The amounts of total n and different organic n forms in the whole soils as well as size fractions generally increased with increasing the amount of compost. In the whole soils, percentage distribution of non-hydrolysable-n and amino sugar-n increased by compost application while the distribution values of the hydrolysable ammonium- n and unidentified-n decreased. The application did not affect the distribution degree of amino acid-n. In the size fractions, the distribution values of most organic n forms increased in the CSA-DP, MSA-DP and FSA-DP fractions by compost application. In the CLA fractions, the amounts and percentage distribution of organic n forms were the highest, although the application caused decreases in their distribution values. These findings indicate that the CLA fraction merit close attention as an important reservoir of various organic n.

关键词： Compost Application Upland and Paddy Fields Soil Organic n Forms Size Fractions

Crystal Structures of Two new Monoprotonated Products of 1,4,7 trimethyl-1,4,7-triazacyclononane: （Me3〔9〕anen3H）(SO3CF3) and （Me3〔9〕anen3H）I

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Chinese Journal of Structural Chemistry 2000年第1期19卷 48-52页

作者： DEnG Dao Lia * zhanG Yan Hui a DAI Cong Yun a ZEnG Hong a YAn Zhi Qing a YE Chang Qing a Ronald ha\|Ge ba (Unilever Research SIOC, 354 Fenglin Road, Shanghai 200032. China) b (Unilever Research Laboratorium, Olivier van noor Unilever Research SIOC 上海 2 0 0 0 32 Unilever Research Laboratorium 荷兰 Vlaardinge

Two new monoprotonated products of macrocyclic polyamine 1,4,7 trimethyl 1,4,7 triazacyclononane(Me 3〔9〕anen 3), (Me 3〔9〕anen 3H)(SO 3CF 3) 1 (C 10 H 22 n 3O 3SF 3, M r =321.36) and (Me 3〔9〕anen 3H)I 2 (C 9H 22 n 3I, M r =299.20) were obtained by the reactions of Me 3〔9〕anen 3 and yttrium triflate or ytterbium diiodide as the unexpected products. The crystal structures of compounds 1 and 2 have been determined. Crystal 1 is orthorhombic, space group P2 12 12 1(#19), a =12.609(3), b=13.531(1), c=9.225(3) , V=1573.9(7)  3, Z=4, D c= 1.356 g/cm 3, μ =2.47 cm -1 , F (000)=680 and R=0.052, R w =0.052 for 807 unique reflections with I>2σ(I) . Crystal 2 belongs to the orthorhombic system with space group P2 12 12 1(#19), a=11.417(2), b=13.099(3), c=8.762(2) , V=1310.5(4)  3, Z=4, D c =1\^516 g/cm 3, μ =24.14 cm -1 , F (000)=600 and R=0.035, R w =0.042 for 1427 unique reflections with I>3σ(I) . The two structures contain the same cyclic framework in which the acid proton is bonded to an amine nitrogen. This proton exhibits strong intramolecular hydrogen bonds with the other two nitrogen atoms. The methyl groups are directed away from the ring cavity. The bond distance between acid proton and an amine nitrogen in compound 2 is extremely short. The bond angles for 1 and 2 also exhibit obvious diversity inside of triazacyclononae.

关键词： formation crystal structure protonation triazacyclononane

A KInETIC APPROACH TO SCALAR MULTI-DIMEnSIOnAL COnSERVATIOn LAWS

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Acta Mathematica Scientia 1996年第2期16卷 218-228页

作者：胡家信 Young Scientists Laboratory of Wuhan Inst. of Math. Sci. Academia Sinica Wuhan 430071 China

This paper gives the kinetic formation of multi-dimensional conservation laws and proves the compactness of velocity averages by employing the compactness theorem in L(loc)(1)(R(n) x R(t)). As a by product, the existe... 详细信息

关键词： conservation law generalized solution kinetic equation