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Effect of 2-butyne-1, 4-diol on silver electrodeposition from 5, 5-dimethyl hydantoin solutions 被引量:1
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作者 LU Junfeng AN Maozhong ZHENG Huanyu 《Rare Metals》 SCIE EI CAS CSCD 2006年第z2期255-259,共5页
The effect of 2-butyne-1, 4-diol on silver electrodeposition process from 5, 5-dimethyl hydantoin solutions was investigated by means of cyclic voltammetric measurement, scanning electron microscopy (SEM) and X-ray di... The effect of 2-butyne-1, 4-diol on silver electrodeposition process from 5, 5-dimethyl hydantoin solutions was investigated by means of cyclic voltammetric measurement, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Cyclic voltammetric studies indicate that the reduction process of silver electrodeposition is influenced by adding 2-butyne-1, 4-diol. Owing to its adsorption on the electrode surface, 2-butyne-1, 4-diol moderately hinders the mass transfer of the silver complexed ions from the bulk solution to the outer limit of the electrode double layer and affects the electrocrystallization step. Scanning electron microscopy analysis reveals that the presence of 2-butyne-1, 4-diol in the electrolyte is beneficial and the silver deposits obtained are smoother, more compact and more leveled. X-ray diffraction analysis of the silver deposits obtained at 0.5 g·L-1 2-butyne-1, 4-diol indicated that the (110) plane is the most preferred plane and is not affected by the presence of 2-butyne-1, 4-diol in the electrolyte. 展开更多
关键词 silver electrodeposition 5 5-dimethyl hydantoin solutions 2-butyne-1 4-diol electrocrystallization
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Mechanical properties and microstructure evolution of solidified copper tailings with hydantoin epoxy resin 被引量:1
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作者 Yong HE Wen-qiang JIANG +5 位作者 Ke-ping CHEN Lian-rong WU Ke-neng ZHANG Zhi-peng YU Xue-ping GAN De-shan FENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第9期3065-3076,共12页
Based on the strength and microstructure tests,the effects of the hydantoin epoxy resin content and curing time on the mechanical properties and microstructure of copper tailings specimens were studied.The results sho... Based on the strength and microstructure tests,the effects of the hydantoin epoxy resin content and curing time on the mechanical properties and microstructure of copper tailings specimens were studied.The results showed that the strength of the solidified specimens was increased to 20.84 MPa with 30 wt.%addition of hydantoin epoxy resin.When the specimens with 10%hydantoin epoxy resin were cured for 7 and 14 d,the strengths were 6.33 and 6.67 MPa respectively,which met the requirements as foundation filler and building materials.The microscopic tests showed that the agglomeration was enhanced and the porosities of the solidified specimens were reduced with increase in the hydantoin epoxy resin content,which could greatly enhance the strength of solidified specimens. 展开更多
关键词 copper tailings hydantoin epoxy resin mechanical properties MICROSTRUCTURE
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New optically active poly(amide-imide)s derived from N,N'-(4,4-diphthaloyl)-bis-L-leucine and hydantoin derivatives:Synthesis and properties
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作者 Khalil Faghihi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第10期1153-1156,共4页
Six new optically active poly(amide-imide)s (5a-f) were synthesized through the direct polycondensation reaction of N,N′-(4,4′- diphthaloyl)-bis-L-leucine (3) with six hydantoin derivatives (4a-f). Tripben... Six new optically active poly(amide-imide)s (5a-f) were synthesized through the direct polycondensation reaction of N,N′-(4,4′- diphthaloyl)-bis-L-leucine (3) with six hydantoin derivatives (4a-f). Tripbenyl phosphite (TPP)/pyridine in the presence of calcium chloride (CaCl2) and N-methyl-2-pyrrolidone (NMP) were successfully applied for direct polycondensation. The polycondensation reactions produce a series of new poly(amide-imide)s (5a-f) in high yields, and inherent viscosity between 0.42 and 0,55 dL/g. The resulting poly(amide-imide)s (5a-f) were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis (TGA and DTG), solubility test and FT-IR spectroscopy. 展开更多
关键词 High performance polymers Poly(amide-imide)s Direct polycondensation hydantoin derivatives
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POLYMERIZATION OF N,N'-(PYROMELLITOYL)-BIS-L-LEUCINE DIACID CHLORIDE WITH HYDANTOIN DERIVATIVES BY MICROWAVE IRRADIATION
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作者 Khalil Faghihi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第4期343-348,共6页
Facile and rapid polycondensation reactions of N,N'-(pyromellitoyl)-bis-L-leucine diacid chloride 1 with eight different derivatives of hydantoin compounds 2a-h were developed by using a domestic microwave oven in... Facile and rapid polycondensation reactions of N,N'-(pyromellitoyl)-bis-L-leucine diacid chloride 1 with eight different derivatives of hydantoin compounds 2a-h were developed by using a domestic microwave oven in the presence of a small amount of polar organic medium such as o-cresol. The polycondensation reactions proceeded rapidly, compared with the conventional solution polycondensation, and was completed within 7-10 min, producing a series of novel optically active poly(amide-imide)s 3a-h with high yield and inherent viscosity of 0.35-0.65 dL/g. All of the above polymers were fully characterized by FT-IR, elemental analyses, inherent viscosity (η inh ), solubility test and specific rotation. Some structural characterization and physical properties of these optically active poly(amide-imide)s are reported. 展开更多
关键词 Microwave-assisted rapid polycondensation Optically active polymers Poly(amide-imide)s hydantoin derivatives N N'-(Pyromellitoyl)-bis-L-leucine diacid chloride
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RAPID SYNTHESIS OF NOVEL OPTICALLY ACTIVE POLY(AMIDE-IMIDE)S DERIVED FROM N,N'-(PYROMELLITOYL)-BIS-L-ALANINE DIACID CHLORIDE AND HYDANTOIN DERIVATIVES UNDER MICROWAVE IRRADIATION
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作者 Khalil Faghihi Azizollah Mirsamie 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第1期63-69,共7页
Eight novel poly(amide-imide)s were synthesized under microwave irradiation by using a domestic microwaveoven from the polycondensation reactions of N.N'-(pyromellitoyl)-bis-L-alanine diacid chloride(1)with eight ... Eight novel poly(amide-imide)s were synthesized under microwave irradiation by using a domestic microwaveoven from the polycondensation reactions of N.N'-(pyromellitoyl)-bis-L-alanine diacid chloride(1)with eight differentderivatives of hydantoin compounds(2a-h)in the presence of a small amount of a polar organic medium such as o-cresol.The polycondensation proceeded rapidly,compared with the conventional solution polycondensation and was completedwithin 8-10 min,producing a series of new poly(amide-imide)s(3a-h)with inherent viscosities about 0.35-0.68 dL/g inhigh yields.The obtained PAIs(3a-h)were fully characterized by means of FT-IR spectroscopy,elemental analyses,inherentviscosity(ηinh),solubility and specific rotation measurements.All of the resulting polymers show optical rotation and areoptically active.Thermal properties of the poly(amide-imide)s were investigated by using thermal gravimetric analysis(TGA). 展开更多
关键词 Microwave-assisted polycondensation Optically active polymers 5 5-Disubstituted hydantoin derivatives.
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Ti(IV) Chloride-Promoted Diastereoselective Conjugate Addition of 1-Enoyl-5-substituted Hydantoins with Allyltrimethylsilane
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作者 Jun-ichi Yamaguchi Kanako Nozaki Abe Takayuki Suyama 《International Journal of Organic Chemistry》 2012年第4期332-335,共4页
Diastereoselective conjugate addition of 1-enoyl-5-substituted hydantoins with allyltrimethylsilane in the presence of Ti(IV) chloride proceeded to give the corresponding allyl adducts in high yield and high diastereo... Diastereoselective conjugate addition of 1-enoyl-5-substituted hydantoins with allyltrimethylsilane in the presence of Ti(IV) chloride proceeded to give the corresponding allyl adducts in high yield and high diastereoselectivity. In order to determine the absolute configuration on the β-position of the acyl group, the hydantoin was removed by hydrolysis of the allyl adducts with a base to give the corresponding carboxylic acid. It was found that the absolute configuration was S on the basis of specific rotation. 展开更多
关键词 hydantoin Conjugate Addition LEWIS Acid ALLYLTRIMETHYLSILANE
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Simple Reduction of Hydantoins with Sodium Borohydride
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作者 Jun-Ichi Yamaguchi Emiko Shibuta Yoshie Oishi 《International Journal of Organic Chemistry》 2014年第5期286-291,共6页
The reduction of various hydantoins with sodium borohydride gave the corresponding 4-hydroxy- 2-imidazolidinones in high yields. In contrast, reduction employing a boron trifluoride etherate-sodium borohydride system ... The reduction of various hydantoins with sodium borohydride gave the corresponding 4-hydroxy- 2-imidazolidinones in high yields. In contrast, reduction employing a boron trifluoride etherate-sodium borohydride system generated 2-imidazolidinones. In both reductions, the reactivity of the hydantoin was dependent on its substituents. The Lewis acid-promoted reactions of a 4-hydroxy-2-imidazolidinone with nucleophiles were also investigated. 展开更多
关键词 hydantoin REDUCTION IMIDAZOLIDINONE
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New oxorhenium (V) complex with an imidazol [NN] /hydantoin [SN] mixed ligand system, and radiochemical behavior of its oxotechnetium (V) complex analog
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作者 N. S. Al-Hokbany R. M. Mahfouz I. J. Al-Jammaz 《Journal of Biophysical Chemistry》 2011年第2期92-101,共10页
A [ReO(Imz)(Hyd)(H2O)2OH] complex was successfully synthesized by the ligand exchange method using oxorhenuim citrate and an imidazole /Hydanton mixed ligand system. Geometry optimization of complex has been carried o... A [ReO(Imz)(Hyd)(H2O)2OH] complex was successfully synthesized by the ligand exchange method using oxorhenuim citrate and an imidazole /Hydanton mixed ligand system. Geometry optimization of complex has been carried out using DFT at the B3LYP/LANL2DZ functional in singlet state. B3LYP predicated infrared spectrum of the geometrically optimized structure using the same level of the theory and the same base set showed good agreement with experimentally observed values. The spin allowed singlet-singlet electronic transition of the [ReO(Imz)(Hyd) (H2O)2OH] complex was calculated with time dependent density function theory (TD-DFT) and the UV-Vis spectra has been discussed on this basis. The complex was characterized using microanalysis and IR, UV-Vis, NMR and mass spectroscopic. The technetium tracer [99mTcO(Imz)(Hyd) (H2O)2OH] has also been synthesized by two methods using 99mTc-gluconate as a precursor or;by direct reduction. The radiochemical purity of the complex was over 95% as measured by thin layer chromatography. In vitro studies showed that the complex possessed good stability under physiological conditions. The partition coefficient indicated that the complex hydrophilic and the electrophoresis results showed that the complex cationic. Biodistrbution in mice showed that the complex accumulated in heart uptake of 9.53±3.87 % ID/gm at 5 min and good retention (6.37±1.21) % ID/gm at 60 min. One hour after the injection, the heart/liver, heart/lung and heart/blood radioactivity ratios were 0.46, 1.04 and 0.56, respectively. These findings indicate that the complex might be suitable for myocardial imaging. 展开更多
关键词 IMIDAZOLE (Imz) hydantoin (Hyd) mixed ligand [ReO]3+ DFT 99mTc-gluconate
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Scope and Limitations of Optical Pure Hydantoins as Chiral Auxiliaries in Asymmetric Mannich Reactions
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作者 CHEN Feng LU Cuifen +2 位作者 NIE Junqi CHEN Zuxing YANG Guichun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2016年第2期219-225,共7页
The Mannich reaction of various 5-substituted and N-acyl substituted chiral hydantoins with a series of aldimines smoothly occurred with full stereochemical control. These Mannich adducts have been cleaved by alcoholy... The Mannich reaction of various 5-substituted and N-acyl substituted chiral hydantoins with a series of aldimines smoothly occurred with full stereochemical control. These Mannich adducts have been cleaved by alcoholysis to afford several synthetically useful chiral building blocks like β-amino esters and β-lactams in good yields and in enantiopure form. 展开更多
关键词 SCOPE LIMITATION hydantoin Chiral auxiliary Mannich reaction
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Synthesis and Antitussive Effect of New Hydantoin Compounds
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作者 ZHANG Qun-li SONG Li-jun WANG En-si 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第1期76-81,共6页
A series of new hydantoin compounds was synthesized with 3-bromo phenylacetic acid and 3,4-dimethylbromobenzene as starting material, 7-bromo-2-tetralone and 2-bromo-5,6,8,9-tetrahydro-7-benzocycloheptenone as interme... A series of new hydantoin compounds was synthesized with 3-bromo phenylacetic acid and 3,4-dimethylbromobenzene as starting material, 7-bromo-2-tetralone and 2-bromo-5,6,8,9-tetrahydro-7-benzocycloheptenone as intermediate and Ullmann reaction, Suzuki reaction and Bucherer-Berg's reaction as key steps. The structures of the key intermediate and target compounds were confirmed by lH NMR, 13C NMR, IR and MS. Bioactivity research showed that target compounds 6a, 6c, 6d, 6e and 15i had significant antitussive effect on the ammonia-induced couch of mice. 展开更多
关键词 hydantoin 2-Bromo-5 6 8 9-tetrahydro-7-benzocycloheptenone Bioactivity 7-Bromo-2-tetralone Anti-tussive effect
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Synthesis of Chiral Hydantoins and Thiazolidinediones via Iridium-Catalyzed Asymmetric Hydrogenation
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作者 Yu Nie Jing Li +1 位作者 Qianjia Yuan Wanbin Zhang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2022年第7期819-824,共6页
Herein,we report an iridium-catalyzed asymmetric hydrogenation of hydantoin and thiazolidinedione derived exocyclic alkenes using our developed BiphPHOX as a ligand.The transformation shows good functional group toler... Herein,we report an iridium-catalyzed asymmetric hydrogenation of hydantoin and thiazolidinedione derived exocyclic alkenes using our developed BiphPHOX as a ligand.The transformation shows good functional group tolerance,and gives the hydrogenated prod-ucts with excellent yields(up to 99%)and enantioselectivities(up to 98%ee).A gram-scale reaction was also carried out,and pro-vided the hydrogenated product in excellent yield with no erosion in enantioselectivity.Finally,the transformation of the hydrogen-ated product provided an efficient approach for the synthesis of the intermediate of a HIV protease inhibitor. 展开更多
关键词 hydantoinS THIAZOLIDINEDIONES Phosphine-oxazoline ligand IRIDIUM Asymmetric catalysis
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端羧基液体丁腈橡胶改性海因环氧树脂性能研究
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作者 王莹 《包装工程》 CAS 北大核心 2023年第13期43-48,共6页
目的采用端羧基液体丁腈橡胶(CTBN)对海因环氧树脂进行增韧改性。方法通过热熔法将不同份数的CTBN添加到海因环氧树脂中,以4,4'–二氨基二苯甲烷为固化剂制备了改性环氧树脂,通过固化动力学研究确定了其固化工艺,考察CTBN用量对改... 目的采用端羧基液体丁腈橡胶(CTBN)对海因环氧树脂进行增韧改性。方法通过热熔法将不同份数的CTBN添加到海因环氧树脂中,以4,4'–二氨基二苯甲烷为固化剂制备了改性环氧树脂,通过固化动力学研究确定了其固化工艺,考察CTBN用量对改性树脂体系的反应活性、力学性能、热性能以及断面微观形貌的影响。结果随着CTBN的加入,改性树脂的固化放热峰向高温方向偏移。CTBN可显著提高树脂体系的断裂伸长率和冲击强度,其热性能基本保持不变。改性树脂的断面呈现两相“海岛”结构。结论CTBN对海因环氧树脂有明显的增韧作用,制备的改性树脂体系可用于金属防腐涂料和胶黏剂等材料。 展开更多
关键词 端羧基液体丁腈橡胶 海因环氧树脂 增韧 热性能
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5-取代海因的消旋过程对化学酶法制备D-氨基酸的影响 被引量:8
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作者 姚忠 郭峰 +3 位作者 李家璜 屠春燕 韦萍 欧阳平凯 《高校化学工程学报》 EI CAS CSCD 北大核心 2002年第6期675-679,共5页
海因酶是化学酶法制备光学活性氨基酸的关键酶,今研究通过采用不同旋光性的底物进行了海因酶底物光学特异性的研究。结果表明,本体系采用的海因酶是D-海因酶,具有严格的光学选择性;提出了L-海因消旋是以混旋海因制备D-氨基酸的重要限速... 海因酶是化学酶法制备光学活性氨基酸的关键酶,今研究通过采用不同旋光性的底物进行了海因酶底物光学特异性的研究。结果表明,本体系采用的海因酶是D-海因酶,具有严格的光学选择性;提出了L-海因消旋是以混旋海因制备D-氨基酸的重要限速步骤;以L-5-甲基海因为对象,研究了L-海因的消旋过程,对其动力学过程进行了分析。研究表明,L-海因消旋符合一级反应动力学过程;并结合实验提出增高温度和pH值均有助于提高转化效率。 展开更多
关键词 消旋过程 化学酶法 制备 D-氨基酸 海因酶 5-单取代海因 生物转化 工艺
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RP-HPLC测定哈蟆油中1-甲基海因的含量 被引量:12
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作者 王永生 张辉 +1 位作者 林喆 王哲 《中国药学杂志》 CAS CSCD 北大核心 2008年第2期146-148,共3页
目的建立哈蟆油中1-甲基海因反相高效液相色谱(RP—HPLC)含量测定方法。方法采用ZORBAX Eclipse XDB—C18柱(4.6mm×150mm,5μm)色谱柱,检测波长为235nm,乙腈-水(10:90)为流动相,流速为0.3mL·min^-1。结果在0.32... 目的建立哈蟆油中1-甲基海因反相高效液相色谱(RP—HPLC)含量测定方法。方法采用ZORBAX Eclipse XDB—C18柱(4.6mm×150mm,5μm)色谱柱,检测波长为235nm,乙腈-水(10:90)为流动相,流速为0.3mL·min^-1。结果在0.32—1.58μg内峰面积与其浓度呈良好的线性关系(r=0.9999),方法的精密度RSD为0.8%。平均回收率为99.5%,RSD为1.3%。结论测定方法简便快捷、精密度高、准确性好,可以作为哈蟆油中1-甲基海因的测定方法,以控制其原料的质量。 展开更多
关键词 哈蟆油 高效液相色谱法 1-甲基海因 含量测定
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杯芳烃衍生物和丙烯酰胺作为复合功能单体的分子印迹聚合物对海因类化合物的选择性识别研究 被引量:11
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作者 卢春阳 王华芳 +4 位作者 何锡文 陈朗星 李文友 曾宪顺 张玉奎 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2005年第10期1820-1824,共5页
以杯[4]芳烃衍生物+丙烯酰胺作为复合功能单体,将其运用到分子印迹技术中,对海因类化合物R-苄基海因进行选择性识别.研究结果表明,由单一的杯[4]芳烃衍生物或丙烯酰胺作为功能单体的分子印迹聚合物对R-苄基海因的选择性均不高,而由杯[4... 以杯[4]芳烃衍生物+丙烯酰胺作为复合功能单体,将其运用到分子印迹技术中,对海因类化合物R-苄基海因进行选择性识别.研究结果表明,由单一的杯[4]芳烃衍生物或丙烯酰胺作为功能单体的分子印迹聚合物对R-苄基海因的选择性均不高,而由杯[4]芳烃衍生物+丙烯酰胺作为复合功能单体的分子印迹聚合物对模板分子具有较高的特异选择性. 展开更多
关键词 分子印迹技术 双功能单体 杯芳烃衍生物 丙烯酰胺 海因类化合物
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5,5-二甲基乙内酰脲无氰镀银工艺的研究 被引量:22
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作者 卢俊峰 安茂忠 +1 位作者 郑环宇 王克迪 《电镀与环保》 CAS CSCD 2007年第1期9-11,共3页
研究了5,5-二甲基乙内酰脲为配位剂的无氰镀银工艺。在讨论镀液组成及工艺条件对镀层外观质量影响的基础上,确定了最佳电镀工艺。阴极电流效率、分散能力、覆盖能力、结合强度等性能的测试表明,5,5-二甲基乙内酰脲无氰镀银工艺在某些方... 研究了5,5-二甲基乙内酰脲为配位剂的无氰镀银工艺。在讨论镀液组成及工艺条件对镀层外观质量影响的基础上,确定了最佳电镀工艺。阴极电流效率、分散能力、覆盖能力、结合强度等性能的测试表明,5,5-二甲基乙内酰脲无氰镀银工艺在某些方面达到甚至优于氰化物镀银工艺,具有推广应用价值。 展开更多
关键词 5 5-二甲基乙内酰脲 无氰镀银 配位剂
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蛋氨酸生产工艺及核心制备技术研究进展 被引量:9
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作者 高文亮 李林凤 +4 位作者 张静静 黎学明 郑道敏 姚如杰 杨成威 《化工进展》 EI CAS CSCD 北大核心 2012年第4期866-872,888,共8页
蛋氨酸被广泛应用于生物、医药、饲料、食品等诸多领域。针对全球蛋氨酸工业急剧发展这一现状,本文简要综述了近年来国内外蛋氨酸的生产工艺,包括生物酶拆分法、微生物发酵法和化学合成法,其中化学合成法主要有氨基内酯法、丙二酸酯法、... 蛋氨酸被广泛应用于生物、医药、饲料、食品等诸多领域。针对全球蛋氨酸工业急剧发展这一现状,本文简要综述了近年来国内外蛋氨酸的生产工艺,包括生物酶拆分法、微生物发酵法和化学合成法,其中化学合成法主要有氨基内酯法、丙二酸酯法、固-液相转移催化法和海因法等,重点讨论了海因水解制备蛋氨酸及蛋氨酸结晶过程中的关键技术,并结合我国蛋氨酸生产的现状展望了蛋氨酸的发展前景:利用石油化工副产品,尽快建立起现代化蛋氨酸企业。 展开更多
关键词 蛋氨酸 海因水解 结晶 生产工艺
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5,5二甲基海因的合成及应用 被引量:6
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作者 陈洛亮 吕国会 +1 位作者 侯玉清 李俊贤 《北京理工大学学报》 EI CAS CSCD 1995年第6期18-22,共5页
以氰化钠、两酮、碳酸铵为原料.采用Bucherer-Bergs环化反应合成了高效健合剂的中间体5,5二甲基海因(DMH),讨论了原料配比、反应温度、反应时间、溶剂及后处理方式等因素对合成及产品性能的影响.应用结果证实... 以氰化钠、两酮、碳酸铵为原料.采用Bucherer-Bergs环化反应合成了高效健合剂的中间体5,5二甲基海因(DMH),讨论了原料配比、反应温度、反应时间、溶剂及后处理方式等因素对合成及产品性能的影响.应用结果证实了以DMH为起始剂合成的键合剂可显著改善硝胺固体推进剂的力学性能及工艺性能. 展开更多
关键词 二甲基海因 Bucherer-Bergs环化反应 键合剂 固体推体剂 力学性能
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乙内酰脲无氰电镀金工艺 被引量:5
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作者 杨潇薇 安茂忠 +2 位作者 冯慧峤 杨培霞 张锦秋 《材料保护》 CAS CSCD 北大核心 2011年第10期45-47,70,共4页
为消除氰化物镀金的危害,提出并研究了以乙内酰脲为配位剂的无氰电镀金工艺。采用扫描电子显微镜(SEM)、原子力显微镜(AFM)对金镀层表面形貌进行观察,采用热震试验测试金镀层结合力,采用硝酸试验测试金镀层的耐蚀性。结果表明:控制金盐1... 为消除氰化物镀金的危害,提出并研究了以乙内酰脲为配位剂的无氰电镀金工艺。采用扫描电子显微镜(SEM)、原子力显微镜(AFM)对金镀层表面形貌进行观察,采用热震试验测试金镀层结合力,采用硝酸试验测试金镀层的耐蚀性。结果表明:控制金盐10 g/L与乙内酰脲100 g/L左右,并加入复配添加剂(0.05 g/L C+0.1mL/L D),镀液无毒、稳定性良好,在阴极电流密度3 A/dm^2,温度40℃下电镀10 min,可得到结晶致密、光亮的金镀层;镀层与镍基体结合牢固,具有良好的耐蚀性。本工艺有望取代氰化物电镀金,具有广阔的应用前景。 展开更多
关键词 乙内酰脲 电镀金 无氰
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超声波作用下5,5-二取代乙内酰脲的合成 被引量:6
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作者 李记太 王树 李立军 《有机化学》 SCIE CAS CSCD 北大核心 1995年第5期558-560,共3页
本文以氰化钠水溶液、碳酸铵和相应的醛或酮为原料,于25°~45℃超声波作用3~4h合成八种5,5-二取代乙内酰脲,收率30.1~100%。与传统方法比较,反应时间缩短,产品收率提高。
关键词 超声波作用 合成 二取代乙内酰脲
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