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Ethylenediamine tetramethylenephosphonic acid as a selective collector for the improved separation of chalcopyrite against pyrite at low alkalinity
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作者 Jianjun Wang Gaogui Jing +3 位作者 Renji Zheng Zijie Huang Wei Sun Zhiyong Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第7期873-882,共10页
Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment a... Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation. 展开更多
关键词 CHALCOPYRITE PYRITE Flotation ethylenediamine tetramethylenephosphonic acid COLLECTOR
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Thermodynamics of solubility of Cu_2(OH)_2CO_3 in ammonia-ammonium chloride-ethylenediamine(En)-water system 被引量:2
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作者 刘维 唐谟堂 +3 位作者 唐朝波 何静 杨声海 杨建广 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第2期336-343,共8页
In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.... In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process. 展开更多
关键词 thermodynamics solubility malachite ammonia ammonium chloride ethylenediamine(en)
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直线切割吻合器在儿童腹腔镜胆总管囊肿根治术Roux-en-Y吻合中的应用
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作者 刘登辉 李勇 +4 位作者 黎明 唐湘莲 黄召 向强兴 周宇翔 《临床小儿外科杂志》 CAS CSCD 北大核心 2024年第3期238-241,共4页
目的探讨直线切割吻合器应用于儿童腹腔镜胆总管囊肿根治术Roux-en-Y吻合中的有效性、安全性及可行性。方法本研究为前瞻性研究,选取2020年1月至2023年1月湖南省儿童医院接受腹腔镜胆总管囊肿根治术Roux-en-Y吻合的34例患儿作为研究对象... 目的探讨直线切割吻合器应用于儿童腹腔镜胆总管囊肿根治术Roux-en-Y吻合中的有效性、安全性及可行性。方法本研究为前瞻性研究,选取2020年1月至2023年1月湖南省儿童医院接受腹腔镜胆总管囊肿根治术Roux-en-Y吻合的34例患儿作为研究对象,按照随机数字表法进行分组,采用直线切割吻合器实施Roux-en-Y吻合术的患儿纳入观察组(n=17),采用传统缝合法实施Roux-en-Y吻合术的患儿纳入对照组(n=17)。记录两组患儿手术时长、术中出血量、术后肠道功能恢复时间、首次进食流质时间、拔除引流管时间、术后住院时间、总住院费用和术后并发症发生率。结果34例均顺利完成手术,无一例中转开放手术。观察组与对照组手术时长[(130.43±31.32)min比(141.51±30.39)min]、术中出血量[(55.45±20.73)mL比(58.62±22.13)mL]差异均无统计学意义(P>0.05);观察组与对照组患儿术后肠道功能恢复时间[(4.03±0.42)min比(4.91±1.13)min]、首次进食流质时间[(3.95±0.61)d比(4.88±1.09)d]、拔除引流管时间[(5.95±0.68)d比(6.65±1.28)d]、术后住院时间[(8.29±2.17)d比(10.33±2.18)d]均短于对照组,差异均有统计学意义(P<0.05);观察组与对照组患儿总住院费用[(34948.17±1019.57)元比(35151.91±1151.15)元]、并发症发生率(1/17比2/17)差异无统计学意义(P>0.05)。结论直线切割吻合器在儿童腹腔镜胆总管囊肿根治术Roux-en-Y吻合中与传统缝合吻合技术的有效性和安全性无明显差异,可促进患儿术后恢复,值得临床推广应用。 展开更多
关键词 胆总管囊肿 腹腔镜 ROUX-en-Y 直线切割吻合器 外科手术 儿童
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腹腔镜Roux-en-Y胃旁路术治疗肥胖糖尿病20例疗效分析
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作者 艾克拜尔·艾力 崔剑昱 +7 位作者 皮尔地瓦斯·麦麦提玉素甫 麦麦提艾力·麦麦提明 伊比提哈尔·买买提艾力 李慧灵 邓秀丽 玉素江·图荪托合提 黎鑫 克力木·阿不都热依木 《临床外科杂志》 2024年第7期733-735,共3页
目的探讨腹腔镜Roux-en-Y胃旁路手术(LRYGB)治疗肥胖糖尿病的临床疗效。方法回顾性分析2012年~2018年新疆维吾尔自治区人民医院微创、疝腹壁外科中心实施LRYGB的20例肥胖糖尿病人的临床资料。结果20例手术均顺利完成,中转开腹病例1例。... 目的探讨腹腔镜Roux-en-Y胃旁路手术(LRYGB)治疗肥胖糖尿病的临床疗效。方法回顾性分析2012年~2018年新疆维吾尔自治区人民医院微创、疝腹壁外科中心实施LRYGB的20例肥胖糖尿病人的临床资料。结果20例手术均顺利完成,中转开腹病例1例。手术时间60~420分钟,平均(150±105.64)分钟,术中失血量20~100ml,平均(37.5±20.99)ml,术后住院时间5~15天,平均(8.25±2.51)天。术后5年内7例(35.00%)发生并发症,均为Clavien-Dindo分级Ⅱ级。术后1、3、5年的体重、体质指数(BMI)、糖化血红蛋白、空腹血糖、总体重减少百分比(TWL%)与术前比较均有改善,差异有统计学意义(P<0.05)。术后5年LRYGB治疗2型糖尿病完全缓解15例(75.00%)。结论LRYGB对肥胖2型糖尿病病人是一种有效的减重及降糖的术式。 展开更多
关键词 腹腔镜胃旁路手术 肥胖 2型糖尿病 减重手术 腹腔镜胃袖状切除术
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STUDIES OF THE INITIATION MECHANISM OF VINYL POLYMERIZATION WITH THE SYSTEM PERSULFATE/N-ALKYL SUBSTITUTED ETHYLENEDIAMINE DERIVATIVES 被引量:1
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作者 郭新秋 丘坤元 冯新德 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第2期165-173,共9页
Effects of N-alkyi substituted ethylenediamine derivatives on vinyl polymerization using persulfate as initiator were studied. The apparent kinetic equations and overall activation energies of acrylamide polymerizatio... Effects of N-alkyi substituted ethylenediamine derivatives on vinyl polymerization using persulfate as initiator were studied. The apparent kinetic equations and overall activation energies of acrylamide polymerization were determined using the above mentioned system as initiator. The promoting activities of different diamine derivatives on vinyl polymerization are in the order of tertiary diamine>secondary diamine>primary diamine. Diamines having methyl groups as the substituent on their nitrogen atom possess higher promoting activity than that of having larger alkyl groups. The initial free radicals produced through the redox reaction of persuifate and diamines were studied by spin strapping technique and ESR spectroscopy. The results obtained confirm the fact that the initial free radicals of the diamine species can initiate vinyl polymerization and become the amino end group of the resulting polymers. 展开更多
关键词 PERSULFATE ethylenediamine Derivatives ESR ACRYLAMIDE Radical Polymerization Redox System
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α-Oxoketene Cyclic S, S-cetals Chemistry-Substitution Reaction of α,α'-Dicinnamoyl Ketene Cyclic S, S-Acetals with Ethylenediamine 被引量:2
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作者 Mei Xin ZHAO Qun LIU +4 位作者 Fu Shun LIANG Jing Fu LIU Bao Zhong ZHAO LianZhong LI (Department of Chemistry, Northeast Normal University, Changchun, 130024)(Department of Chemistry, Jilin Teacher college, Jilin, 131000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第3期231-232,共2页
α,α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α'-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yiel... α,α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α'-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yield under mild conditions. 展开更多
关键词 α α'-dicinnamoyl ketene cyclic S S-acetals ethylenediamine substitution reaction α α'-dicinnamoyl ketene cyclic N N-acetals
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Effect of butanol on flotation separation of quartz from hematite with N-dodecyl ethylenediamine 被引量:7
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作者 Liu Wengang Liu Wenbao +3 位作者 Wang Xinyang Wei Dezhou Zhang Hao Liu Wei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1059-1063,共5页
In order to investigate the effect of butanol on quartz flotation when N-dodecyl ethylenediamine(ND)was used as collector, single mineral flotation and artificial mixed mineral(hematite and quartz were mixed at a mass... In order to investigate the effect of butanol on quartz flotation when N-dodecyl ethylenediamine(ND)was used as collector, single mineral flotation and artificial mixed mineral(hematite and quartz were mixed at a mass ratio of 3:2) separation were conducted in the laboratory. Experimental results indicated that addition of butanol could improve the collecting performance of ND on quartz and enhance the floatability of quartz. Best flotation recovery of quartz was obtained when butanol was mixed with ND at a mass ratio of 1:1. Moreover, the molecular structure of alcohols had a significant effect on mineral recovery. Best separation efficiency could be obtained when tert-butanol was added as it had the largest cross-sectional area. Zeta potential measurements indicated that alcohols could strengthen electrostatic adsorption between quartz and collector. Molecular dynamic simulations revealed that co-adsorption of alcohols along with ND had taken place on the quartz surface, and ND/tert-butyl combinations were more easily absorbed on the quartz surface. 展开更多
关键词 Butanol N-dodecyl ethylenediamine Flotation separation Co-adsorptionQuartz
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Synthesis,Crystal Structure and Antimicrobial Study of N,N,N'-Tris(3-aminopropyl)ethylenediamine Copper(Ⅱ) Diperchlorate 被引量:1
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作者 许兴友 许同桃 +3 位作者 高健 王大奇 陆路德 徐国想 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期121-125,共5页
The title compound [Cu(C11H29N5)](ClO4)2 was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the monoclinic system, space group P21/n with... The title compound [Cu(C11H29N5)](ClO4)2 was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the monoclinic system, space group P21/n with α = 9.405(2), b = 14.495(3), c = 14.715(3) A, β= 90.262(3)°, V=2006.1(7) A^3,M,=493.83,Z=4,F)(000)= 1028,Dc= 1.635 g/cm^3, T= 298(2) K,μ= 1.403 mm^-1 and = 0.71073 A. The was refined to R = 0.0508 and wR = 0. 1250 for 2293 observed reflections with I 〉 2σ(I). The Cu(Ⅱ) atom possesses a five-coordtinate CuN5 environment which shows a slightly distorted square-pyramidal geonetry. Antimicrobial activity study found that the complex is active against Salmonella species, Staphylococcus aureu, Bacillus pumilus and Bacillus coliforms. 展开更多
关键词 N N N'-tris(3-aminopropyl)ethylenediamine copper compound crystal antimicrobial activity
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Crystal Structures of Co(Ⅱ) and Cu(Ⅱ) Complexes and Ammonium Salt Involving Ethylenediamine 被引量:1
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作者 LUO Mei WANG Lei +3 位作者 QIU Jing-Jing ZHANG Jia-Hai LI Qian-Rong YIN Hao 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第12期1835-1840,共6页
The Co(II) complex I and ammonium salt II were synthesized from the direct reaction of 1,2-ethylenediamine and cobaltous acetate tetrahydrate and manganese acetate tetrahydrate in anhydrous ethanol. Treatment of N,N... The Co(II) complex I and ammonium salt II were synthesized from the direct reaction of 1,2-ethylenediamine and cobaltous acetate tetrahydrate and manganese acetate tetrahydrate in anhydrous ethanol. Treatment of N,N'-bis(salicylidene)ethylenediamine with Cu(OAc)2·H2O results in the formation of Cu(II) complex III. C14H37CoNaO8 (I): triclinic, space group P1, a = 8.6296(12), b = 12.0291(17), c = 12.1108(17) A, α = 75.335(2), β = 69.991(2), γ = 72.248(2)°, V= 1109.4(3) A3, Z = 2, ρcaloa = 1.342 g/cm3, the final R= 0.0342 for 4817 observed reflections with I 〉 2σ(I) and Rw = 0.1263 for all data. C6H16N204 (II): space group P1, a = 5.5513(10), b = 5.5589(11), c = 7.4437(14) A, α = 94.332(4), β = 104.497(4), γ = 103.487(4)°,V= 214.06(7) A3, Z = 1, ρcalcd = 1.398 g/cm3, the final R = 0.0431 for 829 observed reflections with I〉 2σ(I) and Rw = 0.1263 for all data. C14H37CuN40 (III), space group P21/n, a = 9.050(9), b = 18.434(17), c = 11.659(11) A, β = 107.134(19)°, V= 1859(3) A3, Z = 4, ρcalcd =1.443 g/cm3, the final R = 0.0616 for 3308 observed reflections (O 〉 2σ(I)) and Rw = 0.1229 for all data. Their structures were all determined by X-ray diffraction, elemental analysis and IR. 展开更多
关键词 Co(II) complex I ammonium salt II 1 2-ethylenediamine cobaltous acetatetetrahydrate manganese acetate tetrahydrate N N'-bis(salicylidene)ethylenediamine Cu(OAc)2·H2O
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"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy 被引量:1
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作者 Xiao-Si Hu Yong Wang +5 位作者 Hong-Tao Pan Chao Zhu Shi-Lei Chen Hui-Chun Liu Qing Pang Hao Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期503-510,共8页
BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require furt... BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application. 展开更多
关键词 Five steps four quadrants Hepatic hilum lymph node Modularized en bloc clearance Laparoscopic pancreaticoduodenectomy
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Selectively leaching Cu(Ⅱ) and Ni(Ⅱ) from acid mine drainage sludge by using ethylenediamine-ammonium sulfate 被引量:1
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作者 李德良 王淀佐 J A Finch 《中国有色金属学会会刊:英文版》 EI CSCD 2002年第6期1176-1179,共4页
A method based on controlling the complexation precipitation equilibrium of metal ions was proposed to selectively recover nickel and copper from hydroxide sludge formed by lime neutralization of acid mine drainage(AM... A method based on controlling the complexation precipitation equilibrium of metal ions was proposed to selectively recover nickel and copper from hydroxide sludge formed by lime neutralization of acid mine drainage(AMD). Ethylenediamine(EDA) and ammonium sulfate were chosen as complex reagent and precipitating reagent, respectively, to dissolve target metal hydroxides from sludge and limit useless metal ions in the pregnant solution. Results from both synthetic and natural samples show the excellent selectivity for the target metals(copper and nickel) against Fe(Ⅲ), Ca(Ⅱ) and Mg(Ⅱ), 99% recovery of Cu(Ⅱ) and Ni(Ⅱ) and shorter leaching time can be reached by this process, and the resultant solution can be used for direct electrowinning. The optimum operating conditions are: pH=9~11, ρ (EDA)=40 g/L, ammonium sulfate 50 g/L, leaching time 5 h(for natural sample) and 2.5 h(for synthetic sludge), liquid to solid ratio being 4 with mechanical stirring at room temperature. 展开更多
关键词 乙二胺 酸性污泥 废物处理 选择性提取
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照明设备抗扰度标准EN IEC 61547:2023新旧版本差异解析
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作者 敖丹 赖明宇 陈俊贤 《环境技术》 2024年第6期242-249,256,共9页
本文主要分析了一般照明用设备电磁兼容抗扰度要求新版本标准EN IEC 61547:2023与上一版本EN 61547:2009的差异,阐述了静电放电测试的工作条件、自镇流灯和道路与街路照明设备的测试要求变化、待机模式的测试要求的增加等主要的差异,总... 本文主要分析了一般照明用设备电磁兼容抗扰度要求新版本标准EN IEC 61547:2023与上一版本EN 61547:2009的差异,阐述了静电放电测试的工作条件、自镇流灯和道路与街路照明设备的测试要求变化、待机模式的测试要求的增加等主要的差异,总结了新版标准中需要注意的事项,展望了未来照明产品的技术发展方向。 展开更多
关键词 电磁兼容 抗扰度 照明设备 IEC 61547 en 61547 标准修订
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EN 50155:2021标准中的型式试验的技术要点解析
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作者 林道祺 金冬磊 +3 位作者 欧仔强 易科技 余延涯 欧钊强 《环境技术》 2024年第6期205-212,共8页
本文对EN 50155:2021中的型式试验要求进行了解读,概述了各试验项目的要求,总结了按标准开展型式试验过程中的注意事项,为业主、设备供应商和第三方检测机构的相关人员在开展型式试验时提供必要的技术参考。
关键词 en 50155:2021 型式试验 轨道交通 机车车辆 电子设备
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Recent Advances in Photoenzymatic Catalysis
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作者 Caiyi Xiang 《International Journal of Organic Chemistry》 2024年第2期69-91,共23页
Photoenzymatic catalysis has become an emerging field in organic synthetic chemistry that provides eco-friendly alternatives to traditional methods. This comprehensive review examines the developing field of photoenzy... Photoenzymatic catalysis has become an emerging field in organic synthetic chemistry that provides eco-friendly alternatives to traditional methods. This comprehensive review examines the developing field of photoenzymatic catalysis, categorized by reaction types and focusing on its application in organic synthesis. This article highlights recent advances in the use of photoenzymatic reactions in carbon-carbon cross-coupling, ketone and alkene reduction, hydroamination, and hydrosulfonylation, mostly by flavin-dependent “ene”-reductases and nitroreductases. In each case, we exemplified the substrate scope that produces products with high yield and enantioselectivity. Additionally, the emerging trends in developing new enzymatic variants and novel reaction pathways that broaden the scope and enhance yield of these reactions were discussed. 展开更多
关键词 Photoenzymatic BIOCATALYSIS BIOCATALYSTS ERED ene”-Reductases Nitroreductases FLAVIN
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En值应用于连续分析仪测定水中氰化物含量不确定度的分析
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作者 江倩文 《广东化工》 CAS 2024年第18期161-163,173,共4页
目的利用SKALAR SAN++连续分析仪测定水中氰化物含量的不确定度及En值检验。方法通过建立数学模型,对标准物质、标准使用液配制、方法多次测量、标准曲线拟合、加标回收率及其检出限等6个分量引入的不确定度进行分析评定,与权威检验机... 目的利用SKALAR SAN++连续分析仪测定水中氰化物含量的不确定度及En值检验。方法通过建立数学模型,对标准物质、标准使用液配制、方法多次测量、标准曲线拟合、加标回收率及其检出限等6个分量引入的不确定度进行分析评定,与权威检验机构所给的检出限的扩展不确定度进行比对,并通过En值检验评价本实验室仪器是否满足方法检测要求。结论本实验室检出限的扩展不确定度U=45.6%(k=2),权威检验机构所给的检出限的扩展不确定度U=50%(k=2),计算|En|=0.15<1,可认为该方法适用于连续流动法测定水中氰化物含量的不确定度评定,并可为在仪器检定周期内建立有效的内部质量控制方法提供参考价值。 展开更多
关键词 连续流动分析 氰化物 不确定度 en检验
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利用|En|值评价不同厂家标准品测定结果的差异性
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作者 张星星 肖瑶 +5 位作者 张娅 尹雅洁 毕研芳 冯洁 李细芬 卢君 《酿酒》 CAS 2024年第4期67-70,共4页
选取三个厂家生产的白酒中主要的26种骨架成分的标准品,分析对比三个厂家的标准品的保留时间、单位浓度的峰面积以及推算出的白酒中各组分的含量的差异性。结果表明,三个厂家标准品定性结果一致,定量结果存在差异,三个厂家26个标准品中... 选取三个厂家生产的白酒中主要的26种骨架成分的标准品,分析对比三个厂家的标准品的保留时间、单位浓度的峰面积以及推算出的白酒中各组分的含量的差异性。结果表明,三个厂家标准品定性结果一致,定量结果存在差异,三个厂家26个标准品中其中8个推算出的样品含量的|En|值>1,则影响检测结果的对比和共享,所以检测用标准品应统一生产厂家。 展开更多
关键词 不同厂家 标准品 |en|值
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Synthesis and Characterization of Free and Copper (II) Complex of N,N′-<i>Bis</i>(Salicylidene)Ethylenediamine for Application in Dye Sensitized Solar Cells
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作者 William Ghann Hany Sobhi +3 位作者 Hyeonggon Kang Tulio Chavez-Gil Fred Nesbitt Jamal Uddin 《Journal of Materials Science and Chemical Engineering》 2017年第6期46-66,共21页
Dye sensitized solar cell represents a promising method for the conversion of solar energy to electric energy. In the present work free N,N'-bis(salicyli-dene)ethylenediamine and its copper (II) complex were synth... Dye sensitized solar cell represents a promising method for the conversion of solar energy to electric energy. In the present work free N,N'-bis(salicyli-dene)ethylenediamine and its copper (II) complex were synthesized, characterized, and investigated for use as dye sensitizers in the fabrication of dye sensitized solar cells. The dyes were characterized using UV-Vis, Steady State Florescence, and Fluorescence Lifetime, Thermogravimetric Analysis, Differential Scanning Calorimetry, and Cyclic Voltammetry. The thermogravimetric analyses of the ligand and the ligand Copper complex demonstrate the stabilizing effect of the copper ion on the ligand complex. Additionally, the copper ion is shown to stabilize the structure, as evidenced by the 150oC increase in the extrapolated onset temperature of the decomposition event. The ligand copper complex is further stabilized by the presence of the copper, which is determined by the 6.34% residue that remained at the end of the thermogravimetric analysis, compared with 0% residue when applying the same condition for the ligand without copper. The current-voltage characteristics of the cells and the electrochemical impedance were determined. The photovoltaic performance of the solar cell devices fabricated using N,N'-bis(salicylidene) ethylenediamine dye was found to be slightly better than those produced from the copper complex. The solar to electric power efficiency of the ligand-based dye sensitized solar cell was 0.14% and that of the copper complex was found to 0.12%. Although the difference in the cell efficiency is quite small, it is obvious that the insertion of Copper into the ligand did not enhance the performance of the solar cells. The photocurrent-photovoltage results are consistent with the absorption spectra that showed a more prominent band for the ligand. The free hydroxyl groups, present in the ligand but absent from the copper complex owing to their coordination with the copper metal, could be responsible for the difference in the performance of the devices. The hydroxyl groups get attached to the TiO2 and facilitate the transfer of electrons. 展开更多
关键词 DSSC COPPER N N'-Bis(Salicylidene)ethylenediamine Dye Titanium Dioxide
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Synthesis and Characterization of MgSb2O6 Trirutile-Type in Low Presence Concentrations of Ethylenediamine
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作者 H. Guillen-Bonilla J. Reyes-Gomez +4 位作者 A. Guillen-Bonilla D. Pozas-Zepeda J. T. Guillen-Bonilla L. Gildo Ortiz M. Flores Martinez 《Journal of Chemistry and Chemical Engineering》 2013年第5期395-401,共7页
The nanoparticles MgSb206 with trirutile-type structure were prepared by colloidal method using ethylanediamine (0.5 and 0.75 mL), following a calcination at 800 ℃. After, those powders were analyzed by x-ray obtai... The nanoparticles MgSb206 with trirutile-type structure were prepared by colloidal method using ethylanediamine (0.5 and 0.75 mL), following a calcination at 800 ℃. After, those powders were analyzed by x-ray obtaining a tetragonal structure with cell parameters, a = 4.64 A and c = 9.25 A and special group P42/mnm. Using a scanning electron microscopy were analyzed the powders calcined at 800 ℃, showing the formation of micro-plates, micro-rods, nanoparticles and morphology as rice grains. Employing a transmission electron microscopy, were found nanostructures hexagonal shaped with sizes of- 33.6 nm (0.5 mL) and 28.6 nm (0.75 mL). 展开更多
关键词 Trirutile ethylenediamine morphology nanostructures.
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Cosmetic Lifting Effect of a Formula Combining Tetrahydroxypropyl Ethylenediamine, Ononis Spinosa and Glycerin as Shown by a New 2-D Imaging Method
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作者 Romain Roure Marion Lanctin +3 位作者 Alex Nkengne Virginie Nollent Liliane Dayan Christiane Bertin 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第3期209-215,共7页
Facial sagging is a major aging change that affects the overall shape of the face. Sagging can negatively impact self-perception and consequently quality of life. In order to fight against this aging sign, we develope... Facial sagging is a major aging change that affects the overall shape of the face. Sagging can negatively impact self-perception and consequently quality of life. In order to fight against this aging sign, we developed a combination of three active ingredients: Tetrahydroxypropyl Ethylenediamine (THPE), Ononis Spinosa extract and Glycerin. In a clinical study, we assessed the efficacy of this association on facial sagging and wrinkles, with a special focus on immediate and lasting effects. Thirty-nine women applied the tested product daily during an eight-week treatment period. Clinical grading by experts and a new, easy to operate, 2-D imaging method were performed at different time points. The 2-D imaging method measured the upper eyelid lifting effect. The results showed an immediate and significant improvement in sagging and wrinkle parameters;these benefits were still observed seven hours after the first application. Results also showed a significant long-term improvement. The lifting effect calculated from the 2-D pictures was 1.08 mm immediately after application;the same method showed a 1.80 mm lifting effect following the eight-week treatment period. These results suggest that a skin care product combining THPE, Ononis Spinosa and Glycerin properties may be used to reduce sagging as well as wrinkles with both immediate and long term benefits. 展开更多
关键词 Facial SAGGING WRINKLES Tetrahydroxypropyl ethylenediamine Immediate EFFECT Long-Lasting EFFECT 2-D Imaging Lift Measurement
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Thoracic giant cell tumor after two total en bloc spondylectomies including one emergency surgery:A case report
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作者 Hai-Feng Liang Hao Xu +3 位作者 Meng-Na Zhan Jian Xiao Juan Li Qin-Ming Fei 《World Journal of Clinical Cases》 SCIE 2024年第16期2894-2903,共10页
BACKGROUND For patients with acute paraplegia caused by spinal giant cell tumor(GCT)who require emergency decompressive surgery,there is still a lack of relevant reports on surgical options.This study is the first to ... BACKGROUND For patients with acute paraplegia caused by spinal giant cell tumor(GCT)who require emergency decompressive surgery,there is still a lack of relevant reports on surgical options.This study is the first to present the case of an acute paraplegic patient with a thoracic spinal GCT who underwent an emergency total en bloc spondylectomy(TES).Despite tumor recurrence,three-level TES was repeated after denosumab therapy.CASE SUMMARY A 27-year-old female patient who underwent single-level TES in an emergency presented with sudden severe back pain and acute paraplegia due to a thoracic spinal tumor.After emergency TES,the patient's spinal cord function recovered,and permanent paralysis was avoided.The postoperative histopathological examination revealed that the excised neoplasm was a rare GCT.Unfortunately,the tumor recurred 9 months after the first surgery.After 12 months of denosumab therapy,the tumor size was reduced,and tumor calcification.To prevent recurrent tumor progression and provide a possible cure,a three-level TES was performed again.The patient returned to an active lifestyle 1 month after the second surgery,and no recurrence of GCT was found at the last follow-up.CONCLUSION This patient with acute paraplegia underwent TES twice,including once in an emergency,and achieved good therapeutic results.TES in emergency surgery is feasible and safe when conditions permit;however,it may increase the risk of tumor recurrence. 展开更多
关键词 Giant cell tumor Thoracic spine Emergency treatment Total en bloc spondylectomy Denosumab therapy Case report
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