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Synthesis of Piperazic Acid-Containing Cyclodepsipeptide Core of Verucopeptin

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Chinese Journal of Chemistry 2023年第17期41卷 2077-2081页

作者： Yuanjun Sun wenhao tang Mei Wang Huxin Ni Ya-Qiu Long Laboratory of Medicinal Chemical Biology College of Pharmaceutical SciencesJiangsu Province Engineering Research Centerof Precision Diagnostics and Therapeutics DevelopmentSoochow UniversitySuzhouJiangsu 215123China

Comprehensive SummaryChemically,N1 nitrogen of piperazic acid is more nucleophilic than N2 nitrogen,but amide bonds predominantly formed at N2 nitrogen are prevalent in piperazic acid-containing natural products,with only one exception of *** two orthogonal protecting groups of nitrogen are often employed to realize selective coupling of N2 nitrogen,resulting in increased synthetic steps and low synthetic ***,we develop selective deprotection of N2-Cbz from the N1,N2-diCbz-piperazic acid-containing peptide to form the N2 amide exclusively,avoiding the tedious orthogonal protection strategy which is commonly applied when the easily-accessible N1,N2-diCbz-piperazic acid is used as the synthetic *** employ this selective-deprotection strategy to achieve an efficient synthesis of piperazic acid-containing cyclodepsipeptide core of verucopeptin with an overall yield of 21%from commercially/readily available building blocks.

关键词： Natural products Piperazic acid Verucopeptin Total synthesis Regioselectivity

Surface engineering for high stable lithium-rich manganese-based cathode materials

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Chinese Chemical Letters 2023年第6期34卷 588-593页

作者： Miaomiao Zhou Jianjun Zhao Xiaodong Wang Ji Shen wenhao tang Yirui Deng Ruiping Liu School of Chemical&Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China State Key Laboratory of Chemical Resources Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing 100083China

Lithium-rich manganese-based material shows great potential as the high specific cathode materials due to its low cost,environmental friendliness,high operating voltage and simple preparation ***,the poor capacity retention and cycling performance caused by its unstable structure during cycling restrict the *** this work,Li_(1.2)Ni_(0.16)Mn_(0.56)Co_(0.08)O_(2)was synthesized utilizing a Coprecipitation method and different amount of La(PO_(3))_(3)(La(PO_(3))_(3)=2 wt%,4 wt%and 6 wt%)was selected as the coating layer to resolve the above *** the calcination process,La(PO_(3))_(3)reacts with impurities such as Li OH and Li_(2)CO_(3)on the lithium-rich surface to reduce the residual lithium on the surface,thus improving the interfacial stability,slowing down the corrosion of the electrolyte,and finally enhancing its electrochemical *** cathode materials coated with 4%of La(PO_(3))_(3)showed the best electrochemical performance in terms of capacity retention and cycling performance compared to the pristine *** high initial discharge capacity of 214.21 m Ah/g and capacity retention of 94.2%after 100 cycles at 0.1 C can be *** work provides an effective strategy to protect the cathode from corrosion and will promote its further practical applications in high specific Li-ion batteries.

关键词： Li-rich layered oxide Li-ion batteries La(PO_(3))_(3)coating Electrochemical performance Structure stability

Cyber-Physical Resilience Enhancement for Power Transmission Systems with Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 844-855页

作者： wenhao Zhang Dongyang Rui Weihong Wang Yang Guo Zhaoxia Jing Wenhu tang School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China Guangzhou Zhiguang Electric Co. Ltd and Zhiguang Research Institute(Guangzhou)Co.LtdGuangzhou 510765China

In a power system, when extreme events occur, such as ice storm, large scale blackouts may be unavoidable. Such small probability but high risk events have huge impact on power systems. Most resilience research in power systems only considers faults on the physical side, which would lead to overly idealistic results. This paper proposes a two-stage cyber-physical resilience enhancement method considering energy storage (ES) systems. The first stage calculates optimal planning of ES systems, and the second stage assesses resilience and enhancement of ES systems during the disaster. In the proposed model, cyber faults indirectly damage the system by disabling monitoring and control function of control center. As a result, when detection and response process of physical faults are blocked by cyber failures, serious load shedding occurs. Such a cyber-physical coupling mechanism of fault, response, restoration process is demonstrated in the modified IEEE Reliable Test System-79 (RTS-79). Simulation results show compared with the physical-only system, the cyber-physical system has a more accurate but degraded resilient performance. Besides, ES systems setting at proper place effectively enhance resilience of the cyber-physical transmission system with less load Shedding.

关键词： Cyber-physical faults energy storage systems resilience enhancement transmission systems

阴茎海绵体注射试验对阴茎血管功能影响的回顾性研究

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北京大学学报（医学版） 2024年第4期56卷 680-686页

作者：陈延李况蒙洪锴张树栋程建星郑仲杰唐文豪赵连明张海涛姜辉林浩成北京大学第三医院泌尿外科北京100191 北京大学第三医院生殖医学中心北京100191 北京大学第三医院超声医学科北京100191 北京大学第一医院泌尿外科北京100034

目的:探究勃起功能障碍(erectile dysfunction,ED)患者年龄、不同激素水平及生化指标对阴茎海绵体血管功能的影响。方法:回顾分析2020年1月至2023年8月于北京大学第三医院生殖医学中心男科进行彩色双频多普勒超声(color duplex Doppler ... 详细信息

目的:探究勃起功能障碍(erectile dysfunction,ED)患者年龄、不同激素水平及生化指标对阴茎海绵体血管功能的影响。方法:回顾分析2020年1月至2023年8月于北京大学第三医院生殖医学中心男科进行彩色双频多普勒超声(color duplex Doppler ultrasonography,CDDU)联合阴茎海绵体注射试验(intracavernosal injection test,ICI)的ED患者的临床资料。使用SPSS 29.0建立数据库进行数据处理,采用多因素Logistic回归进行分析。结果:共纳入700例ED患者,其中ICI结果阴性380例,阳性320例;阴茎海绵体动脉收缩期速度(peak systolic velocity,PSV)5 cm/s者202例,≤5 cm/s者498例;PSV和/或EDV结果异常者264例,PSV和EDV结果均正常者436例。血管性ED患者相较于非血管性ED患者雌二醇和睾酮水平更低(t=-3.546,P<0.001;t=-2.089,P=0.037),高血糖发生率更高(χ^(2)=12.772,P=0.002)。动脉性ED患者相较于非动脉性ED患者年龄更大(t=3.953,P<0.001),高血糖发生率更高(χ^(2)=9.518,P=0.009),雌二醇/睾酮比值更高(t=2.330,P=0.020)。动静脉混合性ED患者相较于均正常者的患者年龄更高(t=3.567,P<0.001),睾酮水平更低(t=-2.288,P=0.022),高血糖发生率更高(χ^(2)=12.877,P=0.002),雌二醇/睾酮比值更大(t=2.096,P=0.037)。多因素Logistic回归分析表明,雌二醇水平升高是血管性ED的保护因素(OR=1.009,95%CI:1.004~1.014),葡萄糖≥7.0 mmol/L是血管性ED的危险因素(OR=0.381,95%CI:0.219~0.661);年龄增长是动脉性ED的危险因素(OR=0.960,95%CI:0.938~0.982);年龄增长(OR=0.976,95%CI:0.958~0.993)、葡萄糖5.6~6.9 mmol/L(OR=0.591,95%CI:0.399~0.876)是动静脉混合性ED的危险因素。结论:高血糖和年龄增长可能使阴茎海绵体血管功能减退,而雌二醇水平升高可能对阴茎海绵体血管功能有保护作用。

关键词：勃起功能障碍彩色双频多普勒超声阴茎海绵体注射血管危险因素

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GPR120激动剂通过β-Arrestin2途径改善高糖诱导的海绵体内皮细胞功能障碍

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中国性科学 2024年第3期33卷 5-10页

作者：郑仲杰程建星唐文豪洪锴姜辉林浩成北京大学第三医院泌尿外科北京100191 北京大学第三医院生殖医学中心北京100191 北京大学第三医院男科北京100191 北京大学第一医院泌尿外科北京100034 北京大学泌尿外科研究所北京100034 北京大学第一医院男科北京100034

目的探讨激活G蛋白偶联受体(GPR)120对高糖诱导的人类阴茎海绵体内皮损伤修复的影响,以期为寻找糖尿病性勃起功能障碍(DMED)新的药物开发靶点提供理论依据。方法收集海绵体植入手术患者术中废弃海绵体组织提取海绵体内皮细胞进行原代培... 详细信息

目的探讨激活G蛋白偶联受体(GPR)120对高糖诱导的人类阴茎海绵体内皮损伤修复的影响,以期为寻找糖尿病性勃起功能障碍(DMED)新的药物开发靶点提供理论依据。方法收集海绵体植入手术患者术中废弃海绵体组织提取海绵体内皮细胞进行原代培养,用高浓度葡萄糖诱导内皮细胞损伤,再以GPR120激动剂治疗,观察对比不同处理的细胞一氧化氮(NO)释放量、细胞迁移、血管生成等功能。结果成功提取人类海绵体内皮细胞进行原代培养并鉴定;发现GPR120在人类海绵体内皮细胞中稳定表达,且与内皮型一氧化氮合酶(eNOS)存在共定位;与高糖损伤组相比,GPR120激动剂治疗组NO释放量、划痕愈合率和血管生成率均显著增加(P<0.05);沉默β-Arrestin2后GPR120激动剂失去原有的治疗效果。结论高糖培养可诱导海绵体内皮细胞功能障碍,GPR120激动剂能够治疗海绵体内皮功能障碍,沉默β-Arrestin2后GPR120激动剂无法改善内皮功能。

关键词：勃起功能障碍糖尿病海绵体内皮细胞 G蛋白偶联受体120 β-Arrestin2

Advanced noble-metal-free bifunctional electrocatalysts for metal-air batteries

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Journal of Materiomics 2022年第2期8卷 454-474页

作者： wenhao tang Boya Li Kewei Teng Xiaodong Wang Ruiping Liu Mengwei Wu Lei Zhang Pengfei Ren Junqing Zhang Ming Feng Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing100083China Department of Mechanical Engineering University of Alaska FairbanksPO Box 755905FairbanksAK99775-5905United States Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun130103China

The sluggish reaction kinetics at the oxygen cathode is one of the important issues hindering the commercialization of the metal-air *** the noble metal can be used as the high-efficiency electrocatalyst to solve the problems to some extent,the high cost and scarcity of these noble-metal catalysts have limited their application in *** this review,we discussed the mecha-nisms of the ORR and OER,and proposed the principles for the bifunctional electrocatalysts firstly,and then the state-of-the-art bifunctional catalysts,including carbon-based materials and transition-metal-based *** the basis of that,the self-supporting 3D noble-metal-free bifunctional ORR/OER catalysts were also ***,the perspectives for the bifunctional electrocatalysts were discussed.

关键词： Bifunctional electrocatalyst Noble-metal free Carbon Transition metal Metal-air battery

Simultaneous bilateral retroperitoneoscopic nephroureterectomy in renal recipients： a single-center experience

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Chinese Medical Journal 2014年第22期127卷 3993-3995页

作者： Ma Lulin Ye Jianfei tang wenhao Department of Urology Peking University Third Hospital Beijing 100191 China

Conventional simultaneous bilateral open nephroureterectomy combined with resection of bladder cuffs seems not optimal for bilateral upper tract urothelial carcinoma （UTUC） in renal transplant and dialysis patients with enormous invasion related to large morbidity,delayed gastrointestinal function,and late recovery.1 This study reports the largest series of minimally invasive procedures of simultaneous bilateral retroperitoneoscopic nephroureterectomy （SBRNU） via a midline lower abdominal incision in renal recipients.

关键词： retroperitoneoscopy bilateral nephroureterectomy urothelial carcinoma renal transplantation

基于猎人猎物优化算法优化BiLSTM的电力负荷短期预测

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山东电力技术 2024年第4期51卷 64-71页

作者：陈晓华吴杰康蔡锦健唐文浩龙泳丞王志平广东电网有限责任公司湛江供电局广东湛江524005 广东工业大学自动化学院广东广州510006 东莞理工学院电子工程与智能化学院广东东莞523808

针对电力负荷由于随机性和非线性等原因导致预测精度不高等问题,基于经验模态分解(empirical mode decomposition,EMD)与猎人猎物优化(hunter-prey optimization,HPO)算法,提出一种优化双向长短期记忆神经网络(bidirectional long short... 详细信息

针对电力负荷由于随机性和非线性等原因导致预测精度不高等问题,基于经验模态分解(empirical mode decomposition,EMD)与猎人猎物优化(hunter-prey optimization,HPO)算法,提出一种优化双向长短期记忆神经网络(bidirectional long short-term memory,BiLSTM)的电力负荷短期预测模型。首先,利用经验模态分解将电力负荷时间序列分解成多个固有模态函数分量和一个残差分量。然后,利用猎人猎物优化算法优化双向长短期记忆神经网络构建HPOBiLSTM预测模型,并将各个固有模态函数分量和残差分量归一化后输入HPO-BiLSTM预测模型中进行预测,把各分量的预测值反归一化后直接相加得到最终的预测结果。最后,选取某地区在2018年3月1日-11日的电力负荷数据进行分析,仿真结果表明,与BiLSTM、HPO-BiLSTM、EMD-BiLSTM、EMD-GA-BiLSTM和EMD-PSO-BiLSTM预测模型相比,EMD-HPO-BiLSTM预测模型的预测精度更高,拟合效果更好。

关键词：双向长短期记忆神经网络猎人猎物优化算法电力负荷短期预测经验模态分解

Microstructure Evolution and Mechanical Properties of Friction Stir Welded Al-Cu-Li Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 855-871页

作者： Peng Chen wenhao Chen Jiaxin Chen Zhiyu Chen Yang tang Ge Liu Bensheng Huang Zhiqing Zhang School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Sichuan Provincial Engineering Research Center of Advanced Materials Manufacturing Technology for Shale Gas High-Efficient Exploitation Southwest Petroleum UniversityChengdu 610500China College of Materials Science and Engineering Chongqing UniversityChongqing 400045China School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China School of Robot Engineering Yangtze Normal UniversityChongqing 408100China

The investigation concentrates on friction stir welded(FSW)Al-Cu-Li alloy concerning its local microstructural evolution and mechanical *** grain features were characterized by electron back scattered diffraction(EBSD)technology,while precipitate characterization was conducted by using transmission electron microscopy(TEM)aligned along[011]Al and[001]Al zone *** mechanical properties are evaluated through micro-hardness and tensile *** can be found that nugget zones exhibit finely equiaxed grains evolved through complete dynamic recrystallization(DRX),primarily occurring in continuous dynamic recrystallization(CDRX)and discontinuous dynamic recrystallization(DDRX).In the thermal-mechanically affected zone(TMAZ),numerous sub-structured grains,exhibiting an elongated morphology,were created due to partial DRX,signifying the dominance of CDRX,DDRX,and geometric dynamic recrystallization(GDRX)in this region.T_(1)completely dissolves in the nugget zone(NZ)leading to the formation of Guinier-Preston zones and increase ofδ′,β′and S′.Conversely,T_(1)partially solubilizes in TMAZ,the lowest hardness zone(LHZ)and heat affected zone(HAZ),and the residual T_(1)undergoes marked coarsening,revealing various T_(1)*** solubilization and coarsening of T_(1)are primary contributors to the degradation of hardness and strength.θ′primarily dissolves and coarsens in NZ and TMAZ,whilst this precipitate largely coarsens in HAZ and LHZ.σ,TB,grain boundary phases(GBPs)and precipitate-free zone(PFZ)are newly generated during FSW.σexists in the TMAZ,LHZ and HAZ,whereas TB nucleates in *** and PFZ mostly develop in LHZ and HAZ,which can cause strain localization during tensile deformation,potentially leading to LHZ joint fracture.

关键词： Al-Cu-Li alloy Friction stir welding Microstructure evolution Mechanical properties