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环保型绝缘气体C5-PFK—分子的构象分析 被引量:1
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作者 王悠 雷志城 +1 位作者 吴司颖 汪雪 《高压电器》 CAS CSCD 北大核心 2021年第3期152-156,共5页
目前,环保型绝缘气体C5-PFK因其良好的环保性能和绝缘强度,在中低压气体绝缘电气设备中有替代SF_(6)的潜力。C5-PFK分子存在可旋转的C-C单键,在体系中彼此运动碰撞或受到外界能量时,几何构型可能会发生变化,进而造成分子的能量或反应活... 目前,环保型绝缘气体C5-PFK因其良好的环保性能和绝缘强度,在中低压气体绝缘电气设备中有替代SF_(6)的潜力。C5-PFK分子存在可旋转的C-C单键,在体系中彼此运动碰撞或受到外界能量时,几何构型可能会发生变化,进而造成分子的能量或反应活性等发生变化。文中利用密度泛函理论B3LYP-D3(BJ)方法、TZP基组及高收敛标准对C5-PFK分子进行几何结构优化,然后进行不同二面角的势能扫描,获取了其中4种可能存在的构象异构体,并对它们的几何构型和能量进行了分析,为后续开展C5-PFK热稳定性、表面吸附等研究工作提供一定的理论参考。 展开更多
关键词 c5-pfk分子 密度泛函理论 构像分析 几何构型
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组合称重法与分压法的C_(5)F_(10)O-PFK/Air混气制备技术研究 被引量:3
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作者 朱会 齐汝宾 +3 位作者 曾晓哲 赫树开 吴倩倩 侯新梅 《化学试剂》 CAS 北大核心 2021年第1期89-93,共5页
制备高精度的C5-PFK/Air混合气体有利于实现对C5-PFK气体-电气性能的科学论证。采用称重法与分压法实现了对不同混合比的C5-PFK/Air混合气体的制备,搭建C5-PFK/Air混气制备实验系统,建立了气相色谱-氢火焰离子化检测器(GC-FID)对制备的C... 制备高精度的C5-PFK/Air混合气体有利于实现对C5-PFK气体-电气性能的科学论证。采用称重法与分压法实现了对不同混合比的C5-PFK/Air混合气体的制备,搭建C5-PFK/Air混气制备实验系统,建立了气相色谱-氢火焰离子化检测器(GC-FID)对制备的C5-PFK/Air混气中C5-PFK定性定量分析的仪器方法,可对实验结果进行溯源校准。研究结果表明,制备13%C5-PFK/Air混合气体的RSD为0.89%,最大示值误差为0.77%;压力为0.5 MPa时,12%~15%浓度范围内C5-PFK/Air混气中C5-PFK峰面积线性拟合系数R^(2)为0.995,一致性良好,可完全汽化;6个月的稳定性考察,气体特性值保持不变,稳定性良好。 展开更多
关键词 称重法 分压法 气相色谱-氢火焰离子化检测器 重复性 均匀性 稳定性 c5-pfk/Air
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2',5'-寡腺苷酸合成酶基础活性对干扰素α治疗慢性丙型肝炎信号传导的影响机制研究 被引量:1
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作者 苏冬娜 陈洪涛 《新乡医学院学报》 CAS 2015年第7期638-641,共4页
目的观察慢性丙型肝炎患者外周血单个核细胞(PBMC)中2',5'-寡腺苷酸合成酶(2-5AS)基础活性对干扰素(IFN)信号分子改变的影响,探讨IFN-α治疗慢性丙型肝炎的作用机制。方法选择60例慢性丙型肝炎患者,抽取外周血分离出PBMC,每份... 目的观察慢性丙型肝炎患者外周血单个核细胞(PBMC)中2',5'-寡腺苷酸合成酶(2-5AS)基础活性对干扰素(IFN)信号分子改变的影响,探讨IFN-α治疗慢性丙型肝炎的作用机制。方法选择60例慢性丙型肝炎患者,抽取外周血分离出PBMC,每份标本进行2-5AS基础活性测定后分为实验组和对照组,对照组PBMC体外培养时不加IFN-α,实验组PBMC体外培养时加入IFN-α。培养24 h后,测定PBMC中2-5AS活性、IFN-α受体(IFN-αR)、信号传导及转录激活因子(Stat)1、Stat2、两面神激酶1(Jak1)和酪氨酸激酶2(Tyk2)等指标。结果实验组PBMC培养24 h后2-5AS活性、Jak1、Stat1、Stat2和Tyk2等表达明显增高(P<0.05),IFN-αR表达降低(P<0.05)。2-5AS基础活性与IFN-α刺激下PBMC中2-5AS、Tyk2和Stat1的表达呈负相关(P<0.05),而与IFN-αR、Jak1和Stat2的表达无相关性(P>0.05)。结论 2-5AS基础活性可下调PBMC对外源性IFN-α的敏感性,Stat1、Tyk2表达降低可能是下调机制发生的原因。 展开更多
关键词 2' 5'-寡腺苷酸合成酶 干扰素 慢性丙型肝炎 信号分子
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环保型气体在充气柜中应用分析与研究 被引量:1
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作者 吴昊 赵瑞影 《电工电气》 2023年第6期55-59,共5页
六氟化硫(SF_(6))气体电气性能良好,但其温室效应严重,使用受到很大限制。通过试验数据对比分析了SF_(6)、N_(2)及干燥空气的理化特性、绝缘性能、分解特性、温升效果,发现干燥空气绝缘性能比N_(2)高10%,但温升效果略低于N_(2),而N_(2)... 六氟化硫(SF_(6))气体电气性能良好,但其温室效应严重,使用受到很大限制。通过试验数据对比分析了SF_(6)、N_(2)及干燥空气的理化特性、绝缘性能、分解特性、温升效果,发现干燥空气绝缘性能比N_(2)高10%,但温升效果略低于N_(2),而N_(2)温升值比SF_(6)温升值高10 K左右。并对比分析了新型环保气体C4-PFN和C5-PFK的理化特性,研究了二者及其混合气体的温升性能及分解特性,给出了各自的应用场合。指出新型环保气体绝缘性能优良,具有良好的应用前景,但存在液化温度高、成本高等问题,对于最佳混合比、气体分子间协同作用有待进一步研究。 展开更多
关键词 六氟化硫气体 新型环保气体 c4-PFN气体 c5-pfk气体 绝缘性能 温升性能
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Achieving high short-circuit current and fill-factor via increasing quinoidal character on nonfullerene small molecule acceptor 被引量:2
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作者 Wenxu Liu Weiping Li +1 位作者 Jiannian Yao Chuanlang Zhan 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期381-384,共4页
Recently, the fused-ring based low band gap (LBG) small molecule acceptors (SMAs) have emerged as efficient nonfullerene acceptors. So far, these LBG SMAs are mainly designed with IC (2-methylene-(3- (1,1 -dicy... Recently, the fused-ring based low band gap (LBG) small molecule acceptors (SMAs) have emerged as efficient nonfullerene acceptors. So far, these LBG SMAs are mainly designed with IC (2-methylene-(3- (1,1 -dicyanomethylene)indanone)) or its analogs, the benzo-type electron-accepting (A) units. Compared to benzene, thiophene is less aromatic and thus the thiophene-involving semiconducting molecule has more quinoidal character, which effectively reduces the energy gap between the highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO). Herein, we show that replacing the IC units in ITIC with the CT (cyclopenta[c]thiophen-4-one-5-methylene-6-(1,1-dicyano- methylene)), a thiophene-fused A unit, the quinoidal character is enhanced from 0.0353 on ITIC to 0.0349 on ITCT, the CT-ended SMA. The increase in the quinoidal character reduces the optical band gap and enhances the near IR absorptivity. When blended with the wide band gap (WBG) polymer donor, PBDB-T, an average power conversion efficiency of 10.99% is obtained with a short-circuit current-density (Jso) of 17.88 mA/cm2 and a fill-factor (FF) of 0.723. For comparisons, theJsc is of 16.92 mA/cm2, FF is of 0.655 and PCE is of 9.94% obtained from the ITIC:PBDB-T device. This case indicates that the replacement of the benzene ring on the IC unit with a more polarizable five-member ring such as thiophene is an effective way to enhance the absorption of the near IR solar photons towards designing high-performance nonfullerene polymer solar cells. 展开更多
关键词 cyclopenta[c]thiophen-4-one-5- methylene-6-(13 -dicyanomethylene) Nonfullerene Small molecule acceptor Polymer solar cell
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一种采用洁净空气绝缘和真空灭弧技术的环境友好型GIS的研究和应用 被引量:15
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作者 李德军 沈威 +1 位作者 KUSCHEL M DEMANN R 《高压电器》 CAS CSCD 北大核心 2019年第2期21-30,共10页
对于高压产品尤其是GIS/AIS开关,SF_6一直被作为主要的灭弧和绝缘介质广泛使用。但因为其非常高的全球变暖潜能(GWP=23 900),在过去几十年人们从没停止过对其替代气体的研究和寻找工作。近年氟化腈(如:C4-PFN即C4F7N)和氟代酮(如:C5-PFK... 对于高压产品尤其是GIS/AIS开关,SF_6一直被作为主要的灭弧和绝缘介质广泛使用。但因为其非常高的全球变暖潜能(GWP=23 900),在过去几十年人们从没停止过对其替代气体的研究和寻找工作。近年氟化腈(如:C4-PFN即C4F7N)和氟代酮(如:C5-PFK即C5F10O)气体及其混合气体作为潜在的SF_6替代气体受到关注和初步应用;同时采用基于真空灭弧室灭弧配合洁净空气绝缘的GIS/AIS开关产品上也被开发并有了实际应用。文中简单总结了现有SF_6替代气体方案的技术现状,并重点介绍一种基于洁净空气绝缘和真空灭弧技术、不采用SF_6和任何氟类气体的GIS产品在研发过程中的一些关键技术,试验发现和最终应用情况。首先通过洁净空气在GIS中不同工况下的绝缘击穿试验和典型缺陷下的局放试验确立该新型GIS的尺寸参数标准;其次比较了GIS隔离开关和接地开关在洁净空气、C4-PFN混合气体、C5-PFK混合气体以及SF_6气体等不同工况下的小电流开合性能,并确定了洁净空气的相关开合特性和相对的优缺点;然后描述了为了满足高压断路器性能对真空灭弧室关键技术的相关改进情况;此外还从环境、安全和运维角度,对使用上述几种气体的开关进行了优劣势评估和讨论;最后结合该类新型开关设备的现场运行经验,认为基于洁净空气绝缘和真空灭弧技术的环境友好型GIS是理想的SF_6 GIS的替代产品。 展开更多
关键词 GIS 全球变暖潜能(GWP) SF6替代气体 洁净空气 真空灭弧室 c4-PFN c5-pfk 绝缘介质和绝缘性能
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Androgen-AR axis in primary and metastatic prostate cancer: chasing steroidogenic enzymes for therapeutic intervention
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作者 Agnese C.Pippione Donatella Boschi +2 位作者 Klaus Pors Simonetta Oliaro-Bosso Marco L.Lolli 《Journal of Cancer Metastasis and Treatment》 CAS 2017年第1期328-361,共34页
Androgens play an important role in prostate cancer(PCa)development and progression.Although androgen deprivation therapy remains the front-line treatment for advanced prostate cancer,patients eventually relapse with ... Androgens play an important role in prostate cancer(PCa)development and progression.Although androgen deprivation therapy remains the front-line treatment for advanced prostate cancer,patients eventually relapse with the lethal form of the disease.The prostate tumor microenvironment is characterised by elevated tissue androgens that are capable of activating the androgen receptor(AR).Inhibiting the steroidogenic enzymes that play vital roles in the biosynthesis of testosterone(T)and dihydrotestosterone(DHT)seems to be an attractive strategy for PCa therapies.Emerging data suggest a role for the enzymes mediating pre-receptor control of T and DHT biosynthesis by alternative pathways in controlling intratumoral androgen levels,and thereby influencing PCa progression.This supports the idea for the development of multi-targeting strategies,involving both dual and multiple inhibitors of androgen-metabolising enzymes that are able to affect androgen synthesis and signalling at different points in the biosynthesis.In this review,we will focus on CYP17A1,AKR1C3,HSD17B3 and SRD5A,as these enzymes play essential roles in all the three androgenic pathways.We will review also the AR as an additional target for the design of bifunctional drugs.Targeting intracrine androgens and AKR1C3 have potential to overcome enzalutamide and abiraterone resistance and improve survival of advanced prostate cancer patients. 展开更多
关键词 AKR1c3 HSD17B3 cYP17A1 SRD5A androgen receptor castration-resistant prostate cancer INHIBITORS bifunctional molecules
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Antibody drug conjugate development in gastrointestinal cancers:hopes and hurdles from clinical trials
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作者 Xiaorong Wu Thomas Kilpatrick Ian Chau 《Cancer Drug Resistance》 2018年第4期204-218,共15页
Gastrointestinal(GI)cancers represent the leading cause of cancer-related mortality worldwide.Antibody drug conjugates(ADCs)are a rapidly growing new class of anti-cancer agents which may improve GI cancer patient sur... Gastrointestinal(GI)cancers represent the leading cause of cancer-related mortality worldwide.Antibody drug conjugates(ADCs)are a rapidly growing new class of anti-cancer agents which may improve GI cancer patient survival.ADCs combine tumour-antigen specific antibodies with cytotoxic drugs to deliver tumour cell specific chemotherapy.Currently,only two ADCs[brentuximab vedotin and trastuzumab emtansine(T-DM1)]have been Food and Drug Administration approved for the treatment of lymphoma and metastatic breast cancer,respectively.Clinical research evaluating ADCs in GI cancers has shown limited success.In this review,we will retrace the relevant clinical trials investigating ADCs in GI cancers,especially ADCs targeting human epidermal growth receptor 2,mesothelin,guanylyl cyclase C,carcinogenic antigen-related cell adhesion molecule 5(also known as CEACAM5)and other GI malignancy specific targets.We will review potential hurdles for their success and provide new perspective for future treatment. 展开更多
关键词 Antibody drug conjugates human epidermal growth receptor 2 MESOTHELIN guanylyl cyclase c carcinogenic antigen-related cell adhesion molecule 5 gastric cancer colorectal cancer pancreatic cancer T-DM1 DS-8201a
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