检索结果-南通市图书馆

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Number rigid determinantal point processes induced by generalized Cantor sets

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2025年

作者： Zhaofeng LIN Yanqi qiu Kai WANG School of Fundamental Physics and Mathematical Sciences HIAS University of Chinese Academy of Sciences School of Mathematical Sciences Fudan University

We consider the Ghosh-Peres number rigidity of translation-invariant determinantal point processes on the real line R, whose correlation kernels are induced by the Fourier transform of the indicators of generalized Cantor sets in the unit interval. Our main results show that for any givenθ∈(0, 1), there exists a generalized Cantor set with Lebesgue measure θ, such that the corresponding determinantal point process is Ghosh-Peres number rigid.

关键词：

腹膜透析对糖尿病尿毒症患者透析效果与生活质量的影响

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

包头医学院学报 2017年第9期33卷 63-65页

作者：李华青丘昭文林冲云福建医科大学附属龙岩第一医院肾内科福建龙岩364000

目的:探讨腹膜透析对糖尿病尿毒症患者透析效果与生活质量的影响。方法:选择2015年8月至2016年8月收治的糖尿病尿毒症患者90例,随机分为观察组和对照组,各45例。对照组采用血液透析治疗,观察组采用腹膜透析治疗。对比两组患者治疗前与治... 详细信息

目的:探讨腹膜透析对糖尿病尿毒症患者透析效果与生活质量的影响。方法:选择2015年8月至2016年8月收治的糖尿病尿毒症患者90例,随机分为观察组和对照组,各45例。对照组采用血液透析治疗,观察组采用腹膜透析治疗。对比两组患者治疗前与治疗12周后血尿素氮(BUN)、血肌酐(SCr)、24 h尿量、24 h尿蛋白水平及生活质量的变化。结果:观察组治疗后BUN、SCr、24 h尿蛋白水平均低于对照组(P<0.05),24 h尿量高于对照组(P<0.05)。观察组治疗后情感职能、生理功能、躯体疼痛、社会功能与总体健康评分均高于同期对照组(P<0.05)。结论:腹膜透析在糖尿病尿毒症患者中具有较好的透析效果,且能够改善生活质量,适于临床推广。

关键词：腹膜透析糖尿病尿毒症透析效果生活质量

羟氯喹联合肾素-血管紧张素系统抑制剂(RASI)对IgA肾病减少蛋白尿的回顾性研究

在线全文

学校读者我要写书评

暂无评论

中国医药指南 2022年第36期20卷 79-81页

作者：丘昭文吴勐邓金秀林春福建医科大学附属龙岩第一医院肾内科福建龙岩364000

目的探讨羟氯喹联合肾素-血管紧张素系统抑制剂(RASI)对IgA肾病治疗减少蛋白尿的临床研究。方法回顾性分析本院2020年10月至2021年12月收治的60例Ig A肾病患者,按照两组患者治疗方案分组,其中对照组(n=37)采用RASI药物治疗,观察组(n=... 详细信息

目的探讨羟氯喹联合肾素-血管紧张素系统抑制剂(RASI)对IgA肾病治疗减少蛋白尿的临床研究。方法回顾性分析本院2020年10月至2021年12月收治的60例Ig A肾病患者,按照两组患者治疗方案分组,其中对照组(n=37)采用RASI药物治疗,观察组(n=23)采用羟氯喹联合RASI治疗。对患者保持至少6个月的随访,对比两组患者尿蛋白、肌酐、血管紧张素Ⅱ、IgA指标变化;同时统计两组患者终点事件发生情况、不良反应发生率。结果治疗前两组患者的尿蛋白、肌酐、血管紧张素Ⅱ、IgA指标水平对比差异不显著(P> 0.05);治疗3个月观察组尿蛋白、血管紧张素Ⅱ、IgA指标水平低于对照组(P 0.05);治疗6个月两组肌酐、血管紧张素Ⅱ、IgA对比差异不显著(P> 0.05),治疗6个月观察组尿蛋白水平低于对照组(P 0.05)。结论在IgA肾病患者的治疗中,采用羟氯喹联合RASI的治疗方案,可有效降低患者尿蛋白水平,从而控制肾病的进展,对患者的远期预后产生积极影响。

关键词： IgA肾病血管紧张素Ⅱ 羟氯喹蛋白尿激素免疫抑制剂

基于MOVES模型的西安市机动车排放清单研究

在线全文

学校读者我要写书评

暂无评论

环境污染与防治 2017年第3期39卷 227-231,235页

作者：郝艳召邓顺熙邱兆文刘强高婵娟徐月云长安大学汽车学院陕西西安710064 长安大学环境科学与工程学院陕西西安710064 中国汽车技术研究中心天津300300

利用本地化修正的MOVES模型结合实地调研数据,测算了西安市机动车排放清单,并对各种污染物的排放分担率进行了分析。结果表明:2012年西安市机动车的PM_(2.5)、PM_(10)、NO_x、总碳氢化合物(THC)、CO、挥发性有机物(VOCs)、NH_3和SO_2排... 详细信息

利用本地化修正的MOVES模型结合实地调研数据,测算了西安市机动车排放清单,并对各种污染物的排放分担率进行了分析。结果表明:2012年西安市机动车的PM_(2.5)、PM_(10)、NO_x、总碳氢化合物(THC)、CO、挥发性有机物(VOCs)、NH_3和SO_2排放总量分别为1 890.48、2 668.89、40 847.75、19 413.30、217 103.04、15 244.86、539.76、2 087.50 t;中型货车和重型货车是PM_(2.5)、PM_(10)和NOx的主要贡献者,小型客车和摩托车是THC、CO和VOCs的主要贡献者,小型客车是NH_3的主要贡献者,小型客车与重型货车对SO_2的排放分担率均较高;柴油车对PM_(2.5)、PM_(10)、NO_x和SO_2的排放分担率高于汽油车,而汽油车对THC、CO、VOCs和NH_3的分担率则高于柴油车;CO在冬季排放最多,其余污染物的排放均在夏季最多,但污染物的季节变化总体上不明显。

关键词：机动车排放清单排放分担率 MOVES模型

在线全文

学校读者我要写书评

暂无评论

双挂汽车列车横向稳定性控制策略

上海大学学报（自然科学版） 2024年第4期30卷 581-594页

作者：赵侃屈怀琨全煜坤宋云龙刘清杰邱兆文中公高远(北京)汽车检测技术有限公司北京101103 长安大学汽车学院西安710064

双挂汽车列车相较于传统半挂车具有更高的运输效率和较低的运输成本,更适合未来公路运输绿色、便捷、高效的发展趋势,但较长的车身总长度和组成单元个数必然会对双挂汽车列车的整车稳定性产生影响.为研究并验证控制策略对双挂汽车列车... 详细信息

双挂汽车列车相较于传统半挂车具有更高的运输效率和较低的运输成本,更适合未来公路运输绿色、便捷、高效的发展趋势,但较长的车身总长度和组成单元个数必然会对双挂汽车列车的整车稳定性产生影响.为研究并验证控制策略对双挂汽车列车横向稳定性的改善情况,基于Trucksim仿真平台搭建双挂汽车列车(B型双挂车)动力学模型,依据运动力学定律建立Simulink双挂汽车列车简化参考模型,分别以动力学和参考模型中各个单元的横摆角速度偏差、横向载荷转移率偏差为输入,结合模糊推理和PID(proportional-integral-derivative control,PID)控制理论构建整车横摆和侧倾稳定性主动控制策略,并根据车辆状态识别结果对控制策略的介入时机进行调整.模拟结果显示:主动控制策略使双挂汽车列车横向稳定性评价参数的波动幅度均有明显减小;各个单元的质心侧偏角峰值降低5.7%∼53%,横摆角速度峰值降低4.9%∼23.8%,侧倾角峰值降低0.5%∼24.9%,质心侧偏角峰值降低0.3%∼32.9%.表明本工作所设计的控制策略对双挂汽车列车的横向稳定性有改善作用,研究结果可为未来双挂汽车列车的横向稳定性研究提供参考.

关键词：双挂汽车列车横向稳定性控制模糊推理 PID 控制差动制动

Novel flexible and transparent microstrip low-pass filter design with Π-shaped DGS

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2025年

作者： Liu Zhaohan Han Yunan qiu Xianbo Li Xianli College of Information Science and Technology， Beijing University of Chemical Technology

This paper proposes a new design for a transparent low-pass filter (LPF) using a flexible PTFE material and metallic copper. The transparent microstrip filter employs an asymmetric Π-shaped structure with dimensions of 260 mm × 13 mm × 0.148 mm， which owns a narrow transition band and achieves an insertion loss of less than 1.0 dB below 0.26 GHz. Furthermore， the insertion loss of the transparent microstrip filter can exceed 30 dB in the stopband of 1.02 GHz to 6.50 GHz. Square holes are added to the copper layer to improve the transparency of the LPF， and the filter performance can be adjusted by changing the square hole area and resolution. Additionally， multiple identical structures are cascaded to increase the insertion loss in the stopband while maintaining the passband. The transparent microstrip LPF has the characteristics of flexibility， high transparency， and significant insertion loss in the stopband， making it suitable for applications that require electromagnetic protection in a clear field of vision.

关键词：

Low-complexity channel estimation for wideband mmWave massive MIMO systems with uniform planar arrays

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2025年

作者： Wang Haotian Liu Lizhou qiu Ling Zhang Lei School of Electronic and Information Engineering， University of Science and Technology of China

Millimeter-wave (mmWave) and massive multiple-input multiple-output (MIMO) are broadly recognized as key enabling technologies for the fifth generation communication systems. In this paper， a low-complexity angle-delay parameters estimation (ADPE) method was put forward for wideband mmWave systems with uniformly planar arrays (UPA). In particular， ADPE method effectively decouples the angle-delay parameters and converts the angle-delay estimation problem into three independent subproblems. Accordingly， the ability to devise an off-grid method based on discrete Fourier transform (DFT) with a closed-form solution for angle-delay estimation and potential path number acquisition can be realized. In actuality， only a limited number of potential paths are close to the true paths influenced by noise. Consequently， the removal of noise paths to acquire the corresponding true path gains through a sparsity adaptive path gains estimation (APGE) method is postulated. Finally， the simulation results substantiate the effectiveness of ADPE and APGE methods.

关键词：

AAV2-PDE6B restores retinal structure and function in the retinal degeneration 10 mouse model of retinitis pigmentosa by promoting phototransduction and inhibiting apoptosis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第8期20卷 2408-2419页

作者： Ruiqi qiu Mingzhu Yang Xiuxiu Jin Jingyang Liu Weiping Wang Xiaoli Zhang Jinfeng Han Bo Lei Henan Eye Hospital Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Eye Institute Henan Academy of Innovations in Medical ScienceZhengzhouHenan ProvinceChina Branch of National Clinical Research Center for Ocular Disease Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Academy of Medical Science Zhengzhou UniversityZhengzhouHenan ProvinceChina

Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell ***,there is no effective treatment for retinitis pigmentosa caused by PDE6B ***-associated virus(AAV)-mediated gene therapy is a promising strategy for treating retinitis *** aim of this study was to explore the molecular mechanisms by which AAV2-PDE6B rescues retinal *** do this,we injected retinal degeneration 10(rd10)mice subretinally with AAV2-PDE6B and assessed the therapeutic effects on retinal function and structure using dark-and light-adapted electroretinogram,optical coherence tomography,and ***-independent acquisition-mass spectrometry-based proteomic analysis was conducted to investigate protein expression levels and pathway enrichment,and the results from this analysis were verified by real-time polymerase chain reaction and western ***2-PDE6B injection significantly upregulated PDE6βexpression,preserved electroretinogram responses,and preserved outer nuclear layer thickness in rd10 *** expressed proteins between wild-type and rd10 mice were closely related to visual perception,and treating rd10 mice with AAV2-PDE6B restored differentially expressed protein expression to levels similar to those seen in wild-type *** Encyclopedia of Genes and Genome analysis showed that the differentially expressed proteins whose expression was most significantly altered by AAV2-PDE6B injection were enriched in phototransduction ***,the phototransductionrelated proteins Pde6α,Rom1,Rho,Aldh1a1,and Rbp1 exhibited opposite expression patterns in rd10 mice with or without AAV2-PDE6B ***,Bax/Bcl-2,p-ERK/ERK,and p-c-Fos/c-Fos expression levels decreased in rd10 mice following AAV2-PDE6B *** data suggest that AAV2-PDE6B-mediated gene therapy promotes phototransduction and inhibits apoptosis by inhibiting the ERK signaling pathway and upr

关键词： apoptosis AAV2-PDE6B ERK1/2 gene therapy phototransduction proteomics rd10 retinitis pigmentosa