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Simple HPLC–UV Analysis of Phenol and Its Related Compounds in Tap Water after Pre-Column Derivatization with 4-Nitrobenzoyl Chloride
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作者 Yasuhiko Higashi 《Journal of Analytical Sciences, Methods and Instrumentation》 2017年第1期18-28,共11页
The purpose of this study is to develop an HPLC-UV (280 nm) method for simultaneous determination of phenol, five chlorophenols (2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol, and 2,4,6-trichl... The purpose of this study is to develop an HPLC-UV (280 nm) method for simultaneous determination of phenol, five chlorophenols (2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol, and 2,4,6-trichlorophenol), and three phenylphenols (2-phenylphenol, 3-phenylphenol, and 4-phenylphenol) in tap water after pre-column derivatization with 4-nitrobenzoyl chloride. Standard curves were obtained after derivatization with 4-nitrobenzoyl chloride in borate buffer (pH 8.5) at 50°C for 1 min. The nine 4-nitrobenzoyl derivatives were well separated in less than 15 min on a Cholester column. Calibration plots were linear in the range of 0.02 ~ 0.12 to 0.9 mg/L, with r2 values ≥0.9928, for all compounds. The lower limits of detection were 0.006 to 0.05 mg/L. The coefficients of variation were less than 12.0%. The recovery values from tap water spiked with a standard mixture of test compounds were satisfactory. While the levels of phenol, five chlorophenols, and three phenylphenols in tap water were below the lower limit of determination, our method is expected to be useful for monitoring and/or identifying environmental water samples that are contaminated with these compounds, i.e., for assessing compliance with the official guidelines of the World Health Organization. 展开更多
关键词 PHENOL CHLOROPHENOL Phenylphenol 4-nitrobenzoyl chloride DERIVATIZATION
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棒状结构NaGdF_(4):Yb^(3+),Er^(3+)上转换发光性能的研究
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作者 李鑫 李玉峰 +1 位作者 张栋梁 王觅堂 《功能材料》 CAS CSCD 北大核心 2024年第1期1130-1140,共11页
以乙二胺四乙酸二钠(EDTD-2Na)为螯合剂,采用水热法合成了棒状结构的NaGdF_(4):Yb^(3+),Er^(3+)纳米粉末。分别借助X射线衍射(XRD)、荧光光谱仪(PL)和扫描显微镜(SEM)对其晶体结构、发光强度和表面形貌进行分析和表征。探究了稀土前驱... 以乙二胺四乙酸二钠(EDTD-2Na)为螯合剂,采用水热法合成了棒状结构的NaGdF_(4):Yb^(3+),Er^(3+)纳米粉末。分别借助X射线衍射(XRD)、荧光光谱仪(PL)和扫描显微镜(SEM)对其晶体结构、发光强度和表面形貌进行分析和表征。探究了稀土前驱体、水热温度和水热时间的实验条件对NaGdF_(4):Yb^(3+),Er^(3+)纳米粉末上转换发光强度的影响;研究了氟源和钠源对NaGdF_(4):Yb^(3+),Er^(3+)晶体形貌和上转换发光强度的改善;同时,采用煅烧处理的方法,进一步探究样品的形貌和发光强度收到的影响。实验结果表明NH4F与NaOH作为氟源和钠源及200℃煅烧1 h得到的棒状结构NaGdF_(4):Yb^(3+),Er^(3+)的发光强度最好,色坐标(CIE)绿色发光强度从84%提升到94.88%。 展开更多
关键词 NaGdF_(4):Yb^(3+) Er^(3+) 上转换发光 稀土氯化物 棒状结构 发光纯度
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Effects of propofol on ammonium chloride-exposed astrocyte morphology and aquaporin-4 expression 被引量:3
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作者 Hanjian Chen Caifei Pan +2 位作者 Peng Guo Yueying Zheng Shengmei Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第5期383-387,共5页
Ammonia induces astrocyte swelling, which is strongly associated with overexpression of aquaporin-4. However, the mechanisms by which ammonia induces astrocyte swelling, and subsequently upregulating aquaporin-4 expre... Ammonia induces astrocyte swelling, which is strongly associated with overexpression of aquaporin-4. However, the mechanisms by which ammonia induces astrocyte swelling, and subsequently upregulating aquaporin-4 expression, remain unknown. In the present study, astrocytes were cultured in vitro and exposed to ammonium chloride (NH4CI), followed by propofol protein kinase C agonist, or antagonist, respectively. Astrocyte morphology was observed by light microscopy, and aquaporin-4 expression was detected by western blot analysis. Results showed that propofol or protein kinase C agonist significantly attenuated the degree of NH4CI-induced astrocyte swelling and inhibited increased aquaporin-4 expression. Propofol treatment inhibited aquaporin-4 overexpression in cultured astrocyte induced by NH4CI; protein kinase C pathway activation is potentially involved. 展开更多
关键词 ammonium chloride AQUAPORIN-4 ASTROCYTES PROPOFOL protein kinase C
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Strontium chloride-catalyzed one-pot synthesis of 4(3H)-quinazolinones under solvent-free conditions 被引量:2
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作者 Min Wang Zhi Guo Song Ting Ting Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1167-1170,共4页
Strontium chloride was used as an efficient and recyclable catalyst in one-pot condensation of anthranilic acid, ortho esters and amines leading to the formation of 4(3H)-quinazolinone derivatives in good yields at ... Strontium chloride was used as an efficient and recyclable catalyst in one-pot condensation of anthranilic acid, ortho esters and amines leading to the formation of 4(3H)-quinazolinone derivatives in good yields at room temperature under solvent-free conditions. 展开更多
关键词 4(3H)-Quinazolinones One-pot synthesis Solvent-free conditions Strontium chloride
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Fe_(3)O_(4)@CTAC粒子的制备及抗菌性能研究
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作者 李楠 许伟坚 +1 位作者 苑金磊 刘长霞 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期76-83,共8页
采用溶剂热法合成了分散性良好的Fe_(3)O_(4)粒子,然后将油酸修饰到Fe_(3)O_(4)粒子表面,再通过疏水作用进行十六烷基三甲基氯化铵(CTAC)包覆,得到Fe_(3)O_(4)@CTAC粒子。采用扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、X射线衍射(XRD... 采用溶剂热法合成了分散性良好的Fe_(3)O_(4)粒子,然后将油酸修饰到Fe_(3)O_(4)粒子表面,再通过疏水作用进行十六烷基三甲基氯化铵(CTAC)包覆,得到Fe_(3)O_(4)@CTAC粒子。采用扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、X射线衍射(XRD)、Zeta电位和振动样品磁强计(VSM)对Fe_(3)O_(4)@CTAC粒子进行了表征,结果表明:Fe_(3)O_(4)粒子表面包覆CTAC后粒径无明显变化,并且仍保持良好的单分散性;Fe_(3)O_(4)@CTAC粒子具有超顺磁性和良好的磁响应性能;Fe_(3)O_(4)@CTAC粒子的Zeta电位较高,分散体系具有较好的稳定性。对Fe_(3)O_(4)@CTAC粒子进行了抗菌性能及磁分离去除菌体测试,结果显示:当Fe_(3)O_(4)@CTAC粒子的含量为50 mg/mL时,与大肠杆菌(E.coli)(105cfu/mL)作用10 min,抗菌率可达100%;Fe_(3)O_(4)@CTAC粒子对E.coli、金黄色葡萄球菌(S.aureus)及枯草芽孢杆菌(B.subtilis)均具有良好的抗菌效果;通过磁场分离可以将Fe_(3)O_(4)@CTAC粒子及吸附的菌体去除。以上结果表明Fe_(3)O_(4)@CTAC粒子是一种快速、高效、可以实现无菌体残留的抗菌剂,具有潜在的应用价值。 展开更多
关键词 磁性Fe_(3)O_(4)粒子 十六烷基三甲基氯化铵(CTAC) Fe_(3)O_(4)@CTAC 大肠杆菌 抗菌性能
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Synthesis of some new bis-3,4-dihydropyrimidin-2(1H)-ones by using silica-supported tin chloride and titanium tetrachloride 被引量:1
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作者 Khodabakhsh Niknam Alireza Hasaninejad Madihe Arman 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期399-402,共4页
Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as ... Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as the catalysts for the synthesis of bisdihydropyrimidin -2(1H)-ones from aromatic dialdehydes,1,3-dicarbonyl compounds and urea at 90℃under solvent-free conditions. 展开更多
关键词 Silica-supported tin chloride Silica-supported titanium tetrachloride Bis-3 4-dihydropyrimidin-2(1H)-one SOLVENT-FREE 1 3-Dicarbonyl compounds
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Synthesis and Crystal Structure of 4-tert-Butyl-6-(4-chlorophenyl)-3,6-dihydro-2H-1,3-thiazin-2-iminium Chloride 被引量:1
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作者 夏林 胡艾希 +2 位作者 曹高 王宇 叶姣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第1期33-36,共4页
The title compound, 4-tert-butyl-6-(4-chlorophenyl)-3,6-dihydro-2H-1,3-thiazin- 2-iminium chloride (C14H18C12N2S), has been synthesized by the reaction of 1-(4-chlorophenyl)- 4,4-dimethylpent-1-en-3-one with thi... The title compound, 4-tert-butyl-6-(4-chlorophenyl)-3,6-dihydro-2H-1,3-thiazin- 2-iminium chloride (C14H18C12N2S), has been synthesized by the reaction of 1-(4-chlorophenyl)- 4,4-dimethylpent-1-en-3-one with thiourea, and its crystal structure was determined by single- crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P211c with a = 16.3064(11), b = 9.4471(6), c = 11.2626 (8)A, β = 108.400(1)°, Z = 4, V = 1646.28(19) A^3, Mr = 317.26, Dc = 1.280 g/cm^3, S = 1.078,μ = 0.510 mm^-1, F(000) = 664, the final R = 0.0514 and wR = 0.1412 for 3210 observed reflections (I 〉 2σ(I)). The thiazine ring system displays a twisted boat conformation, and three N-H,..Cl hydrogen bonds exist in the crystal. The combination of two N-H...Cl hydrogen bonds generate an R2^1 (6) ring. 展开更多
关键词 crystal structure SYNTHESIS 4-tert-butyl-6-(4-chlorophenyl)-3 6-dihydro- 2H- 1 3-thiazin-2-iminium chloride
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4-氯氯苄在CO_(2)下电还原为对氯苯乙酸机制研究
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作者 董文慧 金葆康 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第3期75-83,共9页
对氯苯乙酸在生活生产中有重要应用,到目前为止,大多数合成方法都有烦琐的步骤或使用各种重金属催化剂,成本高且有污染.笔者提出一种在CO_(2)存在下,电化学还原4-氯氯苄制备高价值对氯苯乙酸化合物的方法,同时实现温室气体CO_(2)的利用... 对氯苯乙酸在生活生产中有重要应用,到目前为止,大多数合成方法都有烦琐的步骤或使用各种重金属催化剂,成本高且有污染.笔者提出一种在CO_(2)存在下,电化学还原4-氯氯苄制备高价值对氯苯乙酸化合物的方法,同时实现温室气体CO_(2)的利用与转化.采用4-氯氯苄在含电解质四乙基四氟硼酸铵的乙腈溶剂中恒电位电解合成对氯苯乙酸,电解产物经过核磁、质谱等表征方式确认结构.结果表明,法拉第电解效率为94.0%,转化率为92.9%.利用循环伏安法和原位FT-IR光谱电化学相结合的方法,探究了电化学还原制备对氯苯乙酸的电子转移机制.发现银电极上,CO_(2)气氛下4-氯氯苄的还原过程机制为两电子的不可逆过程,生成的一价阴离子随后进攻CO_(2)生成对氯苯乙酸. 展开更多
关键词 4-氯氯苄 对氯苯乙酸 CO_(2)捕获 现场红外光谱电化学 循环伏安法 电化学还原
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1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯的合成工艺研究
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作者 周瑞 周志旭 +5 位作者 岳朝晨 张娅 李磊 高笛 鹿田 柴慧芳 《广东化工》 CAS 2024年第3期1-3,共3页
1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯是一种重要医药化工中间体。本文以4-甲基-5-硝基吡啶-2-醇为原料,经两步反应得到目标化合物。该合成方法操作简便、后处理操作简便,花费时间少且产物纯度高,产品收率为33.51%;此方法为1,6-二氢-4-... 1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯是一种重要医药化工中间体。本文以4-甲基-5-硝基吡啶-2-醇为原料,经两步反应得到目标化合物。该合成方法操作简便、后处理操作简便,花费时间少且产物纯度高,产品收率为33.51%;此方法为1,6-二氢-4-甲基-6-氧代-3-吡啶磺酰氯的合成提供了合成路线,也为进一步相关类似的合成研究奠定基础。 展开更多
关键词 4-甲基-5-硝基吡啶-2-醇 5-氨基-4-甲基吡啶-2-醇 合成 工艺 医药
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非小细胞肺癌组织中CLCA4的表达情况及与病理和预后的关系
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作者 吴媛媛 刘科 +1 位作者 齐艳丽 童小华 《国际医药卫生导报》 2024年第6期903-907,共5页
目的探究非小细胞肺癌(NSCLC)癌组织中钙激活的氯离子通道A4(CLCA4)的表达情况及其与病理和预后的关系。方法前瞻性选取2019年4月至2022年4月商洛市中心医院收治的106例NSCLC患者进行研究,其中男性64例,女性42例,年龄(56.53±7.54)... 目的探究非小细胞肺癌(NSCLC)癌组织中钙激活的氯离子通道A4(CLCA4)的表达情况及其与病理和预后的关系。方法前瞻性选取2019年4月至2022年4月商洛市中心医院收治的106例NSCLC患者进行研究,其中男性64例,女性42例,年龄(56.53±7.54)岁。均行NSCLC根治性切除术,术后采用免疫组化法检测癌组织及癌旁正常组织中CLCA4的阳性表达情况,采用实时荧光定量逆转录聚合酶链反应(qRT-PCR)检测癌组织及癌旁正常组织中CLCA4 mRNA的相对表达量。根据患者1年随访结局分为无病生存(DFS)组(48例)和非DFS组(58例)。采用t检验和χ^(2)检验对数据进行统计学分析,采用多因素logistic逐步回归模型、生存曲线Kaplan-Meier分析与对数秩检验对患者预后的影响因素进行分析,绘制受试者操作特征曲线(ROC)分析CLCA4与病理和预后的关系。结果癌组织中CLCA4阳性率[45.28%(48/106)]及CLCA4 mRNA的相对表达量[(0.61±0.14)]均低于癌旁正常组织[66.98%(71/106)、(1.07±0.23)](χ^(2)=10.134,P<0.001;t=17.589,P<0.001)。Ⅱ期患者的CLCA4 mRNA表达量高于ⅢA期患者[(0.69±0.15)比(0.61±0.13)](t=2.914,P=0.004)。非DFS组患者中ⅢA期的占比高于DFS组[82.76%(48/58)比33.33%(16/48)](χ^(2)=26.819,P<0.001),CLCA4 mRNA表达量低于DFS组[(0.54±0.13)比(0.69±0.17)](t=5.514,P<0.001)。TNM分期(OR=4.031,95%CI 1.429~11.364,P=0.003)、CLCA4 mRNA表达量(OR=0.310,95%CI 0.109~0.873,P=0.003)是NSCLC患者DFS的影响因素。CLCA4 mRNA表达预测NSCLC患者DFS的灵敏度为0.802(95%CI 0.715~0.893)、特异度为0.809(95%CI 0.721~0.904)、曲线下面积(AUC)为0.857(95%CI 0.782~0.935)。不同CLCA4 mRNA表达组患者的生存曲线比较,差异有统计学意义(Log-rankχ^(2)=6.006,P=0.014)。结论NSCLC患者癌组织中CLCA4表达被抑制,且与病理进展及预后有关。 展开更多
关键词 非小细胞肺癌 钙激活的氯离子通道A4 病理 预后
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Syntheses and Crystal Structures of Cobalt(II) Chloride Complexes of 1,3-Bis(pyridyl-4-ylthio)propan-2-one
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作者 WU Ben-Lai WU Ming-Yan GONG Ya-Qiong CHEN Bai-Quan HONG Mao-Chun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期511-516,共6页
Reactions of 1,3-bis(pyridyl-4-ylthio)propan-2-one L and COCl2·6H2O under different conditions gave two new cobalt(Ⅱ)-chloride-L complexes with distinct structures. Complex [Co(L)2Cl2]·0.5CH3OH}n 1 pr... Reactions of 1,3-bis(pyridyl-4-ylthio)propan-2-one L and COCl2·6H2O under different conditions gave two new cobalt(Ⅱ)-chloride-L complexes with distinct structures. Complex [Co(L)2Cl2]·0.5CH3OH}n 1 prepared by solvothermal treatment is a 3D network, whereas complex {[Co3(L)2Cl6(DMF)4]·2CH3OH·H2O} 2 obtained in DMF-diethyl ether system is a discrete acyclic trimer. Crystal data for 1: space group lbca, a = 15.993(4), b = 18.454(5), c = 21.506(6)A, V= 6347(3) ,A^3, Z = 8, Dc = 1.462 g/cm^3,μ = 1.005 mm^-1, F(000) = 2864, C26.5H26Cl2CoN4O2.5S4, Mr = 698.58, the final R = 0.0499 and wR = 0.1024. Crystal data for 2: space group P1^-, a = 9.9177(6), b = 11.0871 (4), c = 15.5490(12) ,A, α = 83.1834(14),β = 88.910(13), γ = 71.096( 11 )°, V = 1605.8(2) A^3, Z = 1, Dc = 1.362 g/cm^3,μ= 1.194 mm^-1, F(000) = 677, C40H62Cl6Co3N8O9S4, Mr = 1316.71, the final R = 0.0666 and wR =0.1575. 展开更多
关键词 cobalt chloride complex 1 3-bis(pyridyl-4-ylthio)propan-2-one crystal structure
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ABSORPTION SPECTRA OF 4f ELECTRON TRANSITIONS IN THE SYSTEM OF NEODYMIUMSEMIXYLENOL ORANGE-CETYLPYRIDINIUM CHLORIDE
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作者 Nai Xing Wang Department of Chemistry, Shandong University, Jinan, 250100 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期381-382,共2页
In this paper the absorption spectra of Nd-SXO-CPC complex by 4f electron transitions have been studied by zero-order and fourth-order derivative spectrophotome-try. The molar absorptivity is 2.6×10~3 1.mol^(-1).... In this paper the absorption spectra of Nd-SXO-CPC complex by 4f electron transitions have been studied by zero-order and fourth-order derivative spectrophotome-try. The molar absorptivity is 2.6×10~3 1.mol^(-1).cm^(-1) at 585 nm, the fourth-order derivative molar absorptivity is 1.4×10~4 1.mol^(-1).cm^(-1) at 584.5(-) and 587(+) nm. They are 300 times and 1600 times greater than those of the chloride, respectively. 展开更多
关键词 ND THAN ABSORPTION SPECTRA OF 4f ELECTRON TRANSITIONS IN THE SYSTEM OF NEODYMIUMSEMIXYLENOL ORANGE-CETYLPYRIDINIUM chloride
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IR, 1H NMR, Electronic Properties and Conductivity Studies of N1 ,N4-Bis(Diphme)Benzene-l,4-Diamine Chloride Zirconium (IV) [{(Ar)2NC6H5N(Ar)2}ZrCl4] (Ar = C6H5)
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作者 Salem Et. Ashoor 《Journal of Chemistry and Chemical Engineering》 2011年第3期259-263,共5页
A range of new compounds such as N1,N4-bis(diphenylmethlene)benzene-l,4-diamine zirconium (IV) chloride [{(Ar)2NC6HsN(Ar)z}ZrCl4] (Ar = C6H5) complex counting the chelating amine and chloride in position tra... A range of new compounds such as N1,N4-bis(diphenylmethlene)benzene-l,4-diamine zirconium (IV) chloride [{(Ar)2NC6HsN(Ar)z}ZrCl4] (Ar = C6H5) complex counting the chelating amine and chloride in position trans have been prepared. Well-defined NI,N4-bis(diphenylmethlene)benzene-l,4-diamine zirconium (IV) chloride [{(Ar)2NC6H5N(Ar)2}ZrCl4] (Ar = C6H5) was obtained by stoichiometric addition of {(Ar)2NC6H5N(Ar)2} (Ar = C6H5) and {ZrC14} in ethanol at reflex temperature. IR, 1H NMR, electronic properties using hyperchem program study has been improved for this compound such as bond distance, and this compound was also defined as electric conductivity which proves to be useful for conductively compound. 展开更多
关键词 Electronic conductivity NI N4-bis(diphme)benzene-1 4-diamine N1 N4-bis(diphenylmethlene)benzene-1 4-diaminezirconium (IV) chloride.
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Novel Reduction of Arylsulfonyl Chlorides and Sodium Alkyl Thiosulfates to Disulfides with TiCl_4/Zn System
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作者 Zhuang Pin ZHAN Hong Yun GUO and Yong Min ZHANG (Department of Chemistry. Hangzhou University,Hangzhou. 310028) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期471-472,共2页
T1Cl4/Zn system reduces arylsulfonyl chlorides and sedium aldyl thiosulfates to corresponding disulfides in moderate to good yields
关键词 ZN Novel Reduction of Arylsulfonyl chlorides and Sodium Alkyl Thiosulfates to Disulfides with TiCl4/Zn System
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Swelling Properties of New Hydrogels Based on the Dimethyl Amino Ethyl Acrylate Methyl Chloride Quaternary Salt with Acrylic Acid and 2-Methylene Butane-1,4-Dioic Acid Monomers in Aqueous Solutions
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作者 Issa Katime Eduardo Mendizábal 《Materials Sciences and Applications》 2010年第3期162-167,共6页
Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-me... Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-methylene bu-tane-1,4-dioic acid. Hydrogel swelling was measured as a function of the composition of the hydrogel and of the crosslinking agent ratio. High values of swelling have been obtained at very high crosslinking values (【14 wt %) and the equilibrium swelling was reached at very low time (less than 15 minutes). The swelling isotherms consisted of a steep initial portion and then levelled off as asymptotically to the equilibrium swelling limit. The experimental data suggest clearly that the swelling process obeys second-order kinetics. According to this, the kinetics rate constant and the equilibrium water content were determined at different comonomer composition and crosslinker concentration. The calculated kinetic constants ranged from 0.48 to 3.76 &#215;10-2 min-1 for poly (acrylic acid-co-Q9) hydrogels and from 0.68 to 4.0 &#215;10-2 min-1 for poly (2-methylene butane-1,4-dioic acid-co-Q9) hydrogels depending on the hydrogels composition. The diffusion process was evaluated for each hydrogel showing a non-Fickian type diffusion. In all cases was observed a considerable increase in diffusion coefficient as Q9 content increases. 展开更多
关键词 DIMETHYL Amino Ethyl Acrylate Methyl chloride QUATERNARY Salt 2-methylene butane-1 4-Dioic ACID Acrylic ACID SWELLING Diffusion Coefficients Kinetic Order
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PBAT/4-三氟甲基苯甲酰氯酯化秸秆粉制备及性能 被引量:1
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作者 葛铁军 张力 +3 位作者 文起东 文博 刘沛含 唐恺鸿 《工程塑料应用》 CAS CSCD 北大核心 2023年第3期34-39,共6页
为提高秸秆粉与聚己二酸/对苯二甲酸丁二酯(PBAT)的相容性及力学性能,以4-三氟甲基苯甲酰氯(PTF-BOC)为酯化剂,4-二甲氨基吡啶(DMAP)为催化剂,三乙胺为缚酸剂制备酯化秸秆粉。利用转矩流变仪熔融共混制备PBAT和不同PTF-BOC用量秸秆粉的... 为提高秸秆粉与聚己二酸/对苯二甲酸丁二酯(PBAT)的相容性及力学性能,以4-三氟甲基苯甲酰氯(PTF-BOC)为酯化剂,4-二甲氨基吡啶(DMAP)为催化剂,三乙胺为缚酸剂制备酯化秸秆粉。利用转矩流变仪熔融共混制备PBAT和不同PTF-BOC用量秸秆粉的复合材料,采用差示扫描量热仪、旋转流变仪、微机控制电子拉伸试验机和冲击试验机测试了复合材料的热性能、流变性能和力学性能。探究了PTF-BOC用量对秸秆粉中羟基取代度的影响,并对酯化前后秸秆粉进行了傅里叶变换红外结构表征及接触角测试。结果表明,PTF-BOC与秸秆粉成功发生酯化反应,酯化后秸秆粉接触角与PBAT的接触角相近,且较未改性秸秆粉接触角提高70.4%,疏水性提高。酯化秸秆粉与PBAT呈现较好的相容性,当PTF-BOC为秸秆粉质量的55%时,PBAT/酯化秸秆粉复合材料的力学性能最佳,其拉伸强度、断裂伸长率和冲击强度较PBAT/未改性秸秆粉复合材料分别提高28.8%,319%和41.8%。 展开更多
关键词 4-三氟甲基苯甲酰氯 酯化改性 秸秆粉 复合材料
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一锅法合成4-[4,6-二(2,4-二甲苯基)-1,3,5-三嗪-2-基]-1,3-苯二醇
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作者 丁成荣 韩哲 +3 位作者 吴坤 殷燕龙 游兆镭 张国富 《精细石油化工》 CAS 2023年第3期30-33,共4页
以三聚氯氰为起始原料,与间二甲苯和间苯二酚在氯化铝和浓盐酸的催化作用下经两次傅克反应一锅法合成了4-[4,6-二(2,4-二甲苯基)-1,3,5-三嗪-2-基]-1,3-苯二醇,产物结构经^(1)H NMR、^(13)C NMR和ESI-MS进行了确证。采用单因素实验考察... 以三聚氯氰为起始原料,与间二甲苯和间苯二酚在氯化铝和浓盐酸的催化作用下经两次傅克反应一锅法合成了4-[4,6-二(2,4-二甲苯基)-1,3,5-三嗪-2-基]-1,3-苯二醇,产物结构经^(1)H NMR、^(13)C NMR和ESI-MS进行了确证。采用单因素实验考察了催化剂种类、助催化剂用量、反应温度和反应时间对该反应的影响。实验结果表明,较佳的反应条件为:以氯化铝为催化剂,浓盐酸用量为氯化铝质量的6%、第一步反应温度为5℃,第二步反应温度为80℃,4-[4,6-二(2,4-二甲苯基)-1,3,5-三嗪-2-基]-1,3-苯二醇的收率可达91.5%,纯度为99.3%。 展开更多
关键词 三聚氯氰 2-氯-4 6-二(2’ 4’-二甲基苯基)-1 3 5-三嗪 4-[4 6-二(2 4-二甲苯基)-1 3 5-三嗪-2-基]-1 3-苯二醇 傅克反应 三嗪类紫外吸收剂
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Effect of Low Dose Samarium Chloride on Serum Hormone Level in Rat
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作者 王丽华 王绍 +2 位作者 唐毓环 聂毓秀 孙文伟 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第4期305-307,共3页
Low dose of samarium chloride was injected into rat(0.05 mg/kg) every other day through three different routes i.e. peritioneal injection, gastric slysis and caudal vein injection. One month later. Serum GH, THT3, THT... Low dose of samarium chloride was injected into rat(0.05 mg/kg) every other day through three different routes i.e. peritioneal injection, gastric slysis and caudal vein injection. One month later. Serum GH, THT3, THT4 and insulin were determined by using radio-immunity assay. The results demonstrated that both serum GH and insulin raised remarkably in experimental groups. THT4 raised only in peritioneal injection group. Besides these, the four different serum hormones showed no obvious change when the dose of samarium chloride decreased to 0.025 mg/kg with caudal vein injection. 展开更多
关键词 samarium chloride GH insulin THT3 THT4 radioimmunity method
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N'-取代-4-卤代-N-甲基-4'-甲烷磺酰氨基二苯甲酮腙衍生物的合成与生物活性 被引量:5
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作者 刘成荡 夏旭建 +3 位作者 郁林军 邢家华 陈杰 彭伟立 《农药》 CAS 北大核心 2007年第2期97-99,102,共4页
以对硝基苯甲酰氯、卤代苯、甲烷磺酰氯、水合肼等为原料合成4-卤代-N-甲基-4'-甲烷磺酰氨基二苯甲酮腙,后者与酰氯、醛和酮等反应得到21种新型N'-取代-4-卤代-N-甲基-4'-甲烷磺酰氨基二苯甲酮腙衍生物。所得化合物结构均经... 以对硝基苯甲酰氯、卤代苯、甲烷磺酰氯、水合肼等为原料合成4-卤代-N-甲基-4'-甲烷磺酰氨基二苯甲酮腙,后者与酰氯、醛和酮等反应得到21种新型N'-取代-4-卤代-N-甲基-4'-甲烷磺酰氨基二苯甲酮腙衍生物。所得化合物结构均经1H NMR和MS表征;初步生物活性测试表明这些化合物具有良好的杀虫活性。 展开更多
关键词 对硝基苯甲酰氯 二苯甲酮腙 合成 生物活性 杀虫活性
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4-甲基-5-甲酰基噻唑的合成工艺研究 被引量:8
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作者 钟为慧 郭宝铭 +2 位作者 赵永志 孙秀玲 苏为科 《高校化学工程学报》 EI CAS CSCD 北大核心 2009年第3期486-490,共5页
研究了头孢托仑匹酯关键中间体4-甲基-5-噻唑甲醛(1)的合成新工艺。以乙酰乙酸甲酯(2)为起始原料,首先进行α-溴代反应、与硫脲缩合反应,制得2-氨基-4-甲基-5-噻唑甲酸甲酯(3),收率高达96%;其次用廉价的次亚磷酸钠(1.5当量)替代次亚磷酸... 研究了头孢托仑匹酯关键中间体4-甲基-5-噻唑甲醛(1)的合成新工艺。以乙酰乙酸甲酯(2)为起始原料,首先进行α-溴代反应、与硫脲缩合反应,制得2-氨基-4-甲基-5-噻唑甲酸甲酯(3),收率高达96%;其次用廉价的次亚磷酸钠(1.5当量)替代次亚磷酸,进行氨基重氮化还原反应,制得4-甲基-5-噻唑甲酸甲酯(4),收率为75%;最后用硼氢化钾/氯化锂体系(1.5当量)在回流的无水乙醇中进行酯还原反应,所得粗产物不经分离提纯,直接用次氯酸钠(2.0当量)氧化得到目标化合物,收率为62%,反应总收率在44%以上。该过程条件温和,操作简便,后处理简单,具有工业化应用前景。 展开更多
关键词 4-甲基-5-甲酰基噻唑 次亚磷酸钠 硼氢化钾 氯化锂 合成
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