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The Effect of Luteal-Phase Support with Triptrolin Administration on Implantation and Clinical Pregnancy Rate in Assisted Reproductive Technology
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作者 Marzieh Aghahosseini Ashraf Alleyassin +7 位作者 Leili Safdarian Saeedeh Gharahjeh Hojat Saeidi Fatemeh Sarvi Sedigheh Hosseini Nooshin Mohammadi Golamreza Roshandel Jalal Gharajeh 《Open Journal of Obstetrics and Gynecology》 2017年第5期571-580,共10页
Background: Luteal phase support with GnRH agonist administration has been shown to be effective in improving the outcome of assisted reproductive technology. The goal of this study was to evaluate the effect of singl... Background: Luteal phase support with GnRH agonist administration has been shown to be effective in improving the outcome of assisted reproductive technology. The goal of this study was to evaluate the effect of single dose Triptrolin (a GnRH agonist) on the probability of the clinical pregnancy rate following embryo transfer (ET) in assisted reproductive techniques (ART). Methods: In this double blinded randomized clinical trial, 340 infertile women who were candidates for intra-cytoplasmic sperm injection (ICSI) were randomly assigned to receive GnRH agonist (Triptrolin) in the luteal phase or placebo. In the intervention group, 0.1 mg Triptrolin was injected subcutaneously, while the control group received normal saline. The clinical pregnancy and implantation rate were compared between the two groups using chi-2 and t-test. P-values less than 0.05 were considered significant. The registration number of this clinical trial is IRCT 2014030916912N1. Results: Administration of 0.1 mg Triptrolin on day 6 after oocyte pick up showed no superiority over placebo in implantation (16.9% - 14%, P = 0.40) and clinical pregnancy rates (32% - 29%, P = 0.66), but the rate of clinical pregnancy was higher in women who were below 27 years of age and those with PCO. Conclusion: Administration of Triptrolin was not superior to placebo for luteal phase support. 展开更多
关键词 Luteal phase support GNRH AGONIST IMPLANTATION Rate Clinical PREGNANCY
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Oral Dydrogesterone versus Vaginal Micronized Progesterone in Luteal Phase Support after Controlled Ovarian Stimulation Using Long Gonadotropin-Releasing Hormone Agonist in Women Undergoing in Vitro Fertilization/Intracytoplasmic Sperm Injection
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作者 Mohamed A.Ibrahem 《Open Journal of Obstetrics and Gynecology》 2019年第12期1558-1568,共11页
Background:?Luteal phase support is indicated after Controlled Ovarian Stimulation (COS) using Long Gonadotropin-Releasing Hormone Agonist (GnRHa) protocol in Women undergoing in Vitro Fertilization (IVF)/Intracytopla... Background:?Luteal phase support is indicated after Controlled Ovarian Stimulation (COS) using Long Gonadotropin-Releasing Hormone Agonist (GnRHa) protocol in Women undergoing in Vitro Fertilization (IVF)/Intracytoplasmic Sperm Injection (ICSI). Progesterone is widely used for this indication. Objective: The objective of the current trial is to compare both efficacy and safety of oral dydrogesterone and vaginal micronized progesterone in luteal phase support in women undergoing IVF/ICSI using the long GnRHa protocol. Methods: This open-label randomized controlled study conducted at a private fertility and IVF center in Zagazig, Egypt, during the interval between April 2016 and August 2019. The study included women planned to undergo IVF/ICSI for either male factor infertility, tubal factor infertility, or unexplained infertility. Women with pelvic endometriosis, known reduced ovarian reserve, and women who were known to have poor or high response to ovarian stimulation, as well as women who were stimulated using non-long GnRHa protocol were not included. After embryo transfer, eligible women were randomly allocated into one of the two groups: group I, included women who received oral dydrogesterone 10 mg three times per day;and group II, included women who received vaginal micronized progesterone 400 mg twice per day. The primary outcome was live birth rate. The principal secondary outcome was women satisfaction. Results: Five hundred sixty four women were recruited and randomly allocated into two groups: group I [Oral Dydrogesterone Group] (n = 284), and group II [Vaginal Progesterone Group] (n = 280). Live birth rates [72 (25.4%) vs 69 (24.6%), respectively, RR 1.03, 95% CI (0.77 to 1.37)], ongoing pregnancy rates [79 (27.8%) vs 81 (28.9%), respectively, RR 0.96, 95% CI (0.74 to 1.25)], clinical pregnancy rates [97 (34.2%) vs 95 (33.9%), respectively, RR 1.01, 95% CI (0.80 to 1.27)] and miscarriage rates (per clinical pregnancy) [18 (18.6%) vs 14 (14.7%), respectively, RR 1.26, 95% CI (0.66 to 2.38)] were all comparable in both groups. The rates of vaginal burning [4 (1.4%) vs 32 (11.4%), respectively, RR 0.12, 95% CI (0.04 to 0.34)], vaginal bleeding [9 (3.2%) vs 26 (9.3%), respectively, RR 0.34, 95% CI (0.16 to 0.72)] and overall dissatisfaction [15 (5.3%) vs 68 (24.3%), respectively, RR 0.22, 95% CI (0.13 to 0.37)] were significantly lower among women of group I when compared to women of group II. Conclusion: In conclusion, when compared to vaginal micronized progesterone, oral dydrogesterone seems to be associated with comparable live birth, ongoing pregnancy and clinical pregnancy rates, and significantly lower dissatisfaction and side effects rates, when given as luteal phase support in normal responding women undergoing IVF/ICSI using the long GnRHa protocol. 展开更多
关键词 DYDROGESTERONE Micronized PROGESTERONE Luteal phase support IVF ICSI Pregnancy RATE Live BIRTH RATE
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A Novel Family of Catalysts Comprising a Supported Metaland a Supported Aqueous-Phase Catalyst 被引量:3
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作者 ZHU Hejun, DING Yunjie, YAN Li, XIONG Jianmin, LI Xuemin, ZHANG Lianzhong, LIN Peizi, HUANG Shiyu, LIN Liwu (Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, Liaoning, China) 《催化学报》 SCIE CAS CSCD 北大核心 2003年第2期81-82,共2页
关键词 水相催化剂 复合型负载催化剂 金属 催化活性
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Magneli phase titanium sub-oxide conductive ceramic Ti_nO_(2n-1) as support for electrocatalyst toward oxygen reduction reaction with high activity and stability 被引量:3
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作者 伍秋美 阮建明 +1 位作者 周忠诚 桑商斌 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1212-1219,共8页
Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-... Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-reduction method. The electrochemical stability of Tin O2n-1 was investigated and the results show almost no change in the redox region after oxidation for 20 h at 1.2 V(vs NHE) in 0.5 mol/L H2SO4 aqueous solution. The catalytic activity and stability of the Pt/Tin O2n-1 toward the oxygen reduction reaction(ORR) in 0.5 mol/L H2SO4 solution were investigated through the accelerated aging tests(AAT), and the morphology of the catalysts before and after the AAT was observed by transmission electron microscopy. At the potential of 0.55 V(vs SCE), the specific kinetic current density of the ORR on the Pt/Tin O2n-1 is about 1.5 times that of the Pt/C. The LSV curves for the Pt/C shift negatively obviously with the half-wave potential shifting about 0.02 V after 8000 cycles AAT, while no obvious change takes place for the LSV curves for the Pt/Tin O2n-1. The Pt particles supported on the carbon aggregate obviously, while the morphology of the Pt supported on Tin O2n-1 remains almost unchanged, which contributes to the electrochemical surface area loss of Pt/C being about 2times that of the Pt/Tin O2n-1. The superior catalytic stability of Pt/Tin O2n-1 toward the ORR could be attributed to the excellent stability of the Tin O2n-1 and the electronic interaction between the metals and the support. 展开更多
关键词 magneli phase TinO2n-1 support oxygen reduction reaction stability
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THE ASYMMETRIC SYNTHESIS OF AMINO ACIDS UNDER POLYMER-SUPPORTED PHASE TRANSFER CATALYTIC CONDITION
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作者 王咏梅 张政朴 +2 位作者 王真 孟继本 霍奇 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第4期356-361,共6页
The optical alpha-amino acids were synthesized under room temperature by alkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phase transfer conditions using polymer-supported cinchonine ... The optical alpha-amino acids were synthesized under room temperature by alkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phase transfer conditions using polymer-supported cinchonine (or quinine) alkaloids as chiral phase transfer catalysts and dichloromethane as solvent, followed by hydrolysis of the above intermediates introduced to the final products-optical alpha-amino acids. This is a new method for the asymmetric synthesis of alpha-amino acids. The influences of catalyst, temperature, substrates, and organic solvents on the chemical yield and optical purities of products were studied. 展开更多
关键词 asymmetric organic synthesis polymer supported phase transfer catalysts (PS-PTC) alpha-amino acids
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Vapor-phase Nitration of Benzene to Nitrobenzene over Supported Sulfuric Acid Catalyst
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作者 Jing Lin CHEN Wei Guo CHENG +2 位作者 Hong Feng LIU Qing Song LIN Lian Hai LU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期311-314,共4页
Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%)... Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) as nitrating agent, and found that supported sulfuric acid catalyst exhibited a very high catalytic activity. Under the conditions of reaction temperature 160-170℃, space velocity (SV) 1200 h-1, the yield and the space-time yield (STY) of nitrobenzene (NB) based on HNO3 were more than 98% and 0.75 kg穔gcat-1穐-1 over 10% H2SO4/SiO2 (by weight) catalyst respectively. 展开更多
关键词 Nitration (vapor-phase) sulfuric acid (supported catalyst) NITROBENZENE
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Traceless solid-phase synthesis of 3-substituted isoxazoles from polystyrene-supported vinyl selenide
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作者 Qin Xin Shou Ri Sheng +2 位作者 Shu Ying Lin Xiao Ling Liu Xian Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第1期1-3,共3页
A novel facile procedure for traceless solid-phase synthesis of 3-substituted isoxazoles in good yields and with excellent purities using polymer-supported vinyl selenide has been developed.
关键词 Solid phase organic synthesis Polystyrene-supported vinyl selenide Isoxazole
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Solid-phase synthesis of (Z)-allyl iodides from 3-acetoxy-2-methylene-alkanoates with recyclable polymer-supported selenium bromide
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作者 Shou Ri Sheng Ming Gang Hu +2 位作者 Qin Xin Xiao Ling Liu Xian Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第4期377-379,共3页
Reaction of polystyrene-supported lithium selenide with 3-acetoxy-2-methylene-alkanoates afforded the corresponding allyl selenide resins and subsequent cleavage from the polymer by treating with methyl iodide to furn... Reaction of polystyrene-supported lithium selenide with 3-acetoxy-2-methylene-alkanoates afforded the corresponding allyl selenide resins and subsequent cleavage from the polymer by treating with methyl iodide to furnish (Z)-allyl iodides in good yields and high purities. The polymeric selenium reagent can be regenerated and reused. So it is a environmentally benign reagent. 展开更多
关键词 Solid phase organic synthesis Polystyrene-supported selenium bromide (Z)-Allyl iodide
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Solid-phase Synthesis of Vinyl Sulfones Using Polystyrene-supported Selenomethyl Phenyl Sulfone
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作者 ShouRiSHENG WeiZHOU XiaoLingLIU QinXIN, CaiShengSONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期583-584,共2页
The solid-phase preparation of vinyl sulfones via a novel polystyrene-supported selenomethyl phenyl sulfone reagent has been reported.
关键词 Solid-phase organic synthesis polystyrene-supported selenomethyl phenyl sulfone vinyl sulfone.
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固相支撑液液萃取/液相色谱-串联质谱法检测人血清中10种抗精神药物
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作者 刘宇凡 赵晓婵 +5 位作者 张若愚 曾永福 张浩然 刘凯旋 艾连峰 康维钧 《分析测试学报》 北大核心 2026年第2期398-405,共8页
该研究建立了一种快速、高通量测定人血清中10种抗精神药物浓度的液相色谱-串联质谱(LC-MS/MS)法。样品前处理采用固相支撑液液萃取(SLE),以甲基叔丁基醚(MTBE)为洗脱溶剂。萃取液经氮吹浓缩后,用50%甲醇水溶液复溶,并对色谱条件进行了... 该研究建立了一种快速、高通量测定人血清中10种抗精神药物浓度的液相色谱-串联质谱(LC-MS/MS)法。样品前处理采用固相支撑液液萃取(SLE),以甲基叔丁基醚(MTBE)为洗脱溶剂。萃取液经氮吹浓缩后,用50%甲醇水溶液复溶,并对色谱条件进行了优化。结果表明,10种抗精神药物的标准曲线线性关系良好,相关系数均大于0.999。检出限(LOD)为0.002~0.075 ng/mL,定量下限(LOQ)为0.005~0.250 ng/mL,回收率为87.3%~112%,相对标准偏差(RSD)均小于8%,批内及批间RSD均不大于13%,基质效应为87.2%~115%(RSD<15%)。该方法具有操作简便、灵敏度高等特点,可用于血清中10种抗精神病药物的同时测定。 展开更多
关键词 固相支撑液液萃取 抗精神药物 液相色谱-串联质谱法 血清
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基于改进支持向量机的有源配电网单相断线故障检测方法
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作者 吴宇轩 欧阳森 +3 位作者 杨向宇 陈汉栋 黎人玮 廖键 《发电技术》 2026年第1期185-194,共10页
【目的】断线故障的及时、准确检测对保障配电网的正常安全运行至关重要,而目前的单相断线故障检测的传统判据在有源配电网中的应用存在一定的局限性,因此,提出了一种基于改进支持向量机对多种电气特征量进行融合的单相断线故障检测方... 【目的】断线故障的及时、准确检测对保障配电网的正常安全运行至关重要,而目前的单相断线故障检测的传统判据在有源配电网中的应用存在一定的局限性,因此,提出了一种基于改进支持向量机对多种电气特征量进行融合的单相断线故障检测方法。【方法】首先,建立了兼具启动判据、传统判据、有源判据的电气特征量指标体系。其次,通过开关量化法对启动判据进行处理。然后,通过核主成分分析方法从启动判据以外的特征指标体系中筛除低贡献率的特征指标。最后,将降维后的数据输入支持向量机,通过麻雀搜索算法完成支持向量机参数优化,得到断线故障检测模型。【结果】在改进IEEE15节点模型上进行的仿真算例表明,所提方法可将有效实现特征量的降维,较单一判据提升了8.87%的检测准确率。【结论】该方法解决了单相断线故障检测的传统判据容易失效的问题,能有效完成不同场景下的故障检测。 展开更多
关键词 有源配电网 单相断线 支持向量机 麻雀搜索算法 核主成分分析
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基于Phase^2数值模拟的巷道支护参数优化研究 被引量:3
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作者 王富林 杨东辉 《煤炭技术》 CAS 北大核心 2017年第1期37-39,共3页
结合某矿回采巷道地质和技术条件,利用Phase^2数值模拟软件建立了不同锚杆支护参数的模型,通过分析巷道变形及应力分布特征,研究了不同锚杆间距和长度时巷道支护效果。结果表明:Phase^2数值模拟可以为巷道支护参数优化设计提供有效参考... 结合某矿回采巷道地质和技术条件,利用Phase^2数值模拟软件建立了不同锚杆支护参数的模型,通过分析巷道变形及应力分布特征,研究了不同锚杆间距和长度时巷道支护效果。结果表明:Phase^2数值模拟可以为巷道支护参数优化设计提供有效参考,优选支护方案效果良好,有效维护了巷道的稳定性。 展开更多
关键词 巷道支护 优化设计 数值分析 phase^2
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Pregnancy outcomes following supplementation of single dose GnRH agonist to sustain the luteal phase in antagonist fresh embryo transfer cycles:A multicentric prospective cohort study
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作者 Tatapudi S V Parvathi Devi Alka Gahlot +3 位作者 Sangita Sharma Manisha Choudhary Ravikant Soni Meeta Sharma 《Asian pacific Journal of Reproduction》 2023年第4期162-169,共8页
Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in ... Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in antagonist protocol fresh embryo transfer cycles.Methods:This prospective,multicentric,cohort study included total 140 women,70 in each group.Controlled ovarian stimulation was carried out as per fixed GnRH antagonist protocol.The trigger was given with hCG.In vitro fertilization/intracytoplasmic sperm injection(IVF/ICSI)was performed and day-3 embryos were transferred.Patients were divided into groups 1 and 2 based on computer generated randomization sheet.Six days following oocyte retrieval,group 1 received 0.2 mg decapeptyl subcutaneously in addition to regular progesterone support while group 2 received progesterone only.Luteal support was given for 14 days to both groups;if pregnancy was confirmed luteal support was continued till 12 weeks of gestation.The clinical pregnancy rate was the primary outcome.The implantation rate,miscarriage rate,live birth delivery rate,and multiple pregnancy rates were the secondary outcomes.Results:A total of 140 patients were analysed,70 in each group.Clinical pregnancy rates(47.1%vs.35.7%;P=0.17),implantation rates(23.4%vs.18.1%,P=0.24),live birth delivery rates(41.4%vs.27.1%,P=0.08),and multiple pregnancy rates(21.2%vs.16.0%,P=0.74)were higher in group 1 than in group 2.Group 1 had a lower miscarriage rate than group 2(5.7%vs.8.6%;P=0.75).However,these differences were not statistically significant between the two groups.Conclusions:Administration of a single dose of GnRH agonist in addition to regular natural micronized vaginal progesterone as luteal support in GnRH antagonist protocol cycles marginally improves implantation rates,clinical pregnancy rates,and live birth delivery rates.However,more studies with higher sample sizes are needed before any conclusive statements about GnRH agonist as luteal phase support can be made. 展开更多
关键词 GnRH agonist TRIPTORELIN IVF Ovum pick up Luteal phase support Antagonist protocol Cleavage stage Fresh embryo transfer Live birth delivery rate
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Phase2软件在隧洞开挖围岩支护时机中的应用 被引量:6
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作者 何欣 曹怀园 +1 位作者 刘永智 刘洁玉 《西北水电》 2015年第3期49-53,共5页
新奥法支护理论允许围岩变形,"适时"支护,能够保证围岩稳定的前提下,减少支护措施。文章利用phase2软件,引入应力释放法和弹性模量折减法解决"适时"的问题,将新奥法理论应用于德尔西水电站工程引水隧洞支护结构设计... 新奥法支护理论允许围岩变形,"适时"支护,能够保证围岩稳定的前提下,减少支护措施。文章利用phase2软件,引入应力释放法和弹性模量折减法解决"适时"的问题,将新奥法理论应用于德尔西水电站工程引水隧洞支护结构设计中,采用量化、清晰易懂的方式证明了合理地选择支护时机可以优化支护结构、减少工程投资,对隧洞工程支护结构设计具有实际意义。 展开更多
关键词 隧洞 支护时机 新奥法 位移 phase2 德尔西水电站
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具有三相电流不平衡治理功能的柔性互联装置控制研究
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作者 徐千禧 赵杨阳 +2 位作者 陈雪妮 于英俊 由蕤 《电气传动》 2026年第2期88-96,共9页
基于电力电子器件的柔性互联装置(FID)可实现配电台区间的功率互济,并可在配电台区故障后进行负荷转供。针对配电台区日益突出的三相不平衡问题,在FID对配电台区进行功率互济的基础上,提出了对配电台区进行三相电流不平衡治理的控制策略... 基于电力电子器件的柔性互联装置(FID)可实现配电台区间的功率互济,并可在配电台区故障后进行负荷转供。针对配电台区日益突出的三相不平衡问题,在FID对配电台区进行功率互济的基础上,提出了对配电台区进行三相电流不平衡治理的控制策略,提高了设备利用率。首先介绍了柔性互联装置的结构、数学模型及运行模式。其次,在原有FID对配电台区进行功率互济基础上,提出一种兼具三相电流不平衡治理功能的控制策略,对负荷三相不平衡电流进行补偿,实现三相平衡。最后,通过Matlab/Simulink仿真及StarSim硬件在环半实物实验对提出控制策略的有效性和可行性进行了验证。 展开更多
关键词 柔性互联装置 功率互济 配电台区 三相不平衡
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Palladium nanoclusters immobilized on defective nanodiamond-graphene core-shell supports for semihydrogenation of phenylacetylene 被引量:3
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作者 Fei Huang Zhimin Jia +3 位作者 Jiangyong Diao Hua Yuan Dangsheng Su Hongyang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第6期31-36,共6页
We report a nanocarbon material with nanodiamond(ND) core and graphene shell(ND@G) as a support for Pd nanocatalysts. The designed catalyst performed good selectivity of styrene(85.2%) at full conversion of phenylacet... We report a nanocarbon material with nanodiamond(ND) core and graphene shell(ND@G) as a support for Pd nanocatalysts. The designed catalyst performed good selectivity of styrene(85.2%) at full conversion of phenylacetylene and superior stability under mild conditions. Supported Pd catalysts are characterized by means of high resolution transmission electron microscopy(HRTEM), Raman, X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and H2 temperature-programmed reduction(H2-TPR).The results clearly show that formation of the strong metal-support interaction(SMSI) between Pd nanoclusters and the defective graphene shell helpfully modifies the selectivity and stability of the Pd-based catalysts. 展开更多
关键词 Selective HYDROGENATION PALLADIUM nano clusters NANOCARBON support Liquid-phase HYDROGENATION
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Prediction of elevator traffic flow based on SVM and phase space reconstruction 被引量:4
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作者 唐海燕 齐维贵 丁宝 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第3期111-114,共4页
To make elevator group control system better follow the change of elevator traffic flow (ETF) in order to adjust the control strategy,the prediction method of support vector machine (SVM) in combination with phase spa... To make elevator group control system better follow the change of elevator traffic flow (ETF) in order to adjust the control strategy,the prediction method of support vector machine (SVM) in combination with phase space reconstruction has been proposed for ETF.Firstly,the phase space reconstruction for elevator traffic flow time series (ETFTS) is processed.Secondly,the small data set method is applied to calculate the largest Lyapunov exponent to judge the chaotic property of ETF.Then prediction model of ETFTS based on SVM is founded.Finally,the method is applied to predict the time series for the incoming and outgoing passenger flow respectively using ETF data collected in some building.Meanwhile,it is compared with RBF neural network model.Simulation results show that the trend of factual traffic flow is better followed by predictive traffic flow.SVM algorithm has much better prediction performance.The fitting and prediction of ETF with better effect are realized. 展开更多
关键词 support vector machine phase space reconstruction prediction of elevator traffic flow RBF neural network
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Polystyrene-supported Benzyl Selenide: An Efficient Reagent for Highly Stereocontrolled Synthesis of Substituted Olefins
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作者 Wei Ming XU Li Ming YU Xian HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第4期335-337,共3页
Polystyrene-supported benzyl selenide has been prepared. This novel reagent was treated with LDA to produce a selenium stabilized carbanion, which reacted with alkyl halide, followed by selenoxide syn-elimination, to... Polystyrene-supported benzyl selenide has been prepared. This novel reagent was treated with LDA to produce a selenium stabilized carbanion, which reacted with alkyl halide, followed by selenoxide syn-elimination, to give substituted olefins stereospecificly. 展开更多
关键词 Solid phase synthesis polystyrene-supported benzyl selenide substituted olefins.
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Polystyrene-supported Selenomethyl-sulfonates: Efficient Reagents for Stereocontrolled Synthesis of Substituted Vinyl Sulfones
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作者 WeiMingXU LuLingWU XianHUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第9期1047-1049,共3页
Polystyrene-supported selenomethyl-sulfonates have been prepared. These novel reagents were treated with LDA to produce selenium stabilized carbanions, which reacted with alkyl halide and epoxides, followed by selenox... Polystyrene-supported selenomethyl-sulfonates have been prepared. These novel reagents were treated with LDA to produce selenium stabilized carbanions, which reacted with alkyl halide and epoxides, followed by selenoxide syn-elimination, to give E-vinyl sulfones and -hydroxy-substituted-E-vinyl sulfones respectively. 展开更多
关键词 Solid phase synthesis polystyrene-supported selenomethyl-sulfonates vinyl sulfones.
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Study on the Active Phases of Ni-W System Hydrotreating Catalysts
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作者 Shi Yahua, Qu Lianglong, Wu Dingjun, Jin Zeming, Li Dadong Part of the work were done by Xue Yongfang, and Sun Naijian. (Research Institute of Petroleum Processing, Beijing 100083) 《石油学报(石油加工)》 EI CAS CSCD 北大核心 1997年第S1期52-57,共6页
StudyontheActivePhasesofNiWSystemHydrotreatingCatalystsShiYahua,QuLianglong,WuDingjun,JinZeming,LiDadong(Res... StudyontheActivePhasesofNiWSystemHydrotreatingCatalystsShiYahua,QuLianglong,WuDingjun,JinZeming,LiDadong(ResearchInstituteo... 展开更多
关键词 HYDROTREATING CATALYST Ni W carbon support ACTIVE phase
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