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Chinese Journal of Chemistry 2024年第3期42卷 271-275页

作者： Yannan Zhu haoran jiang Yi-Ning Wang Faculty of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu224051 China

A phosphine-catalyzed [4+3] annulation between dinucleophilic indole derivatives and Morita−Baylis−Hillman (MBH) carbonates was discovered by using the N1 and N4′/C4′ nucleophilicities of the indole precursors,in which indoles act as four atom synthons. This protocol provides an efficient and facile access to indole-1,2-fused 1,4-diazepinones and azepines in good to high yields in one step,which illustrates potential synthetic utilities in drug discovery.

关键词： Phosphine catalysis [4+3]Annulation Indole derivatives Nitrogen heterocycles Organocatalysis

Boosting cycling stability by regulating surface oxygen vacancies of LNMO by rapid calcination

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Nano Research 2024年第4期17卷 2671-2677页

作者： haoran jiang Cuihua Zeng Wei Zhu Jiawei Luo Zhedong Liu Jingchao Zhang Rui Liu Yunhua Xu Yanan Chen Wenbin Hu School of Materials Science and Engineering Tianjin UniversityTianjin 300072China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Spinel LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)has attracted intensive interest for lithium-ion battery due to its high voltage and high energy ***,severe capacity fade attributed to unstable surface structure has hampered its *** vacancies(OVs)tend to occur in the surface of the material and lead to surface structure reconstruction,which deteriorates the battery performance during electrochemical ***,we utilize high-temperature-shock(HTS)method to synthesize LNMO materials with fewer surface *** calcination drives lower surface OVs concentration,reducing the content of Mn^(3+)and surface reconstruction layers,which is beneficial to obtain a stable crystal *** LNMO material synthesized by HTS method delivers an initial capacity of 127 mAh·g^(-1) at 0.1 C and capacity retention of 81.6%after 300 cycles at 1 C,and exhibits excellent performance at low temperature.

关键词： ultrafast synthesis oxygen vacancy LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)cathode high-temperature-shock lithium-ion batteries

Approaching Ultimate Synthesis Reaction Rate of Ni-Rich Layered Cathodes for Lithium-Ion Batteries

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Nano-Micro Letters 2024年第10期16卷 392-402页

作者： Zhedong Liu Jingchao Zhang Jiawei Luo Zhaoxin Guo haoran jiang Zekun Li Yuhang Liu Zijing Song Rui Liu Wei-Di Liu Wenbin Hu Yanan Chen School of Materials Science and Engineering Tianjin UniversityTianjin 300072People's Republic of China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590People's Republic of China Australian Institute of Bioengineering and Nanotechnology The University of QueenslandSt LuciaQLD 4072Australia

Nickel-rich layered oxide LiNi_(x)Co_(y)MnzO_(2)(NCM,x+y+z=1)is the most promising cathode material for high-energy lithium-ion ***,conventional synthesis methods are limited by the slow heating rate,sluggish reaction dynamics,high energy consumption,and long reaction *** overcome these chal-lenges,we first employed a high-temperature shock(HTS)strategy for fast synthesis of the NCM,and the approaching ultimate reaction rate of solid phase transition is deeply investigated for the first *** the HTS process,ultrafast average reaction rate of phase transition from Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2) to Li-containing oxides is 66.7(%s^(-1)),that is,taking only 1.5 *** ultrahigh heating rate leads to fast reaction kinetics,which induces the rapid phase transition of NCM *** HTS-synthesized nickel-rich layered oxides perform good cycling performances(94%for NCM523,94%for NCM622,and 80%for NCM811 after 200 cycles at 4.3 V).These findings might also assist to pave the way for preparing effectively Ni-rich layered oxides for lithium-ion batteries.

关键词： Nickel-rich layered oxides High-temperature shock Solid reaction kinetics Phase transition Reaction rate

自复位预制节段拼装中空夹层钢管混凝土桥墩地震易损性分析

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震灾防御技术 2024年第3期19卷 613-628页

作者：梁晓姜浩然李芳芳天津城建大学天津市土木建筑结构防护与加固重点实验室天津300384 中石化南京工程有限公司南京210049 天津大学建筑工程学院天津300350

为评估自复位预制节段拼装中空夹层钢管混凝土(Concrete-filled Double Skin Steel Tubular,CFDST)桥墩在地震动作用下的易损性,本研究基于现有的低周反复荷载试验数据,采用有限元分析方法,选用墩顶水平位移角和残余位移角2个指标作为... 详细信息

为评估自复位预制节段拼装中空夹层钢管混凝土(Concrete-filled Double Skin Steel Tubular,CFDST)桥墩在地震动作用下的易损性,本研究基于现有的低周反复荷载试验数据,采用有限元分析方法,选用墩顶水平位移角和残余位移角2个指标作为评估标准进行定量分析。针对3种不同类型地震动(远场、近场无脉冲和近场有脉冲),分别建立了关于水平位移角和残余位移角2个指标的易损性曲线,并分析了不同损伤指标和地震动类型对其地震易损性的影响。研究结果表明,在自复位预制节段拼装CFDST桥墩地震易损性分析中,仅采用水平位移角作为损伤指标是安全可靠的;相比远场地震动和近场无脉冲型地震动而言,近场脉冲型地震动对自复位预制节段拼装CFDST桥墩的变形和自复位有显著影响。

关键词：桥梁抗震预制节段拼装桥墩中空夹层钢管混凝土地震动地震易损性

中国儿童及青少年遗尿症患病率的Meta分析

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中国循证医学杂志 2024年第9期24卷 1052-1060页

作者：王文王喆姜浩然王明月郑三霞山东中医药大学第一临床医学院济南250355 山东中医药大学针灸推拿学院济南250355 河南中医药大学儿科医学院郑州450046 山东中医药大学第二附属医院儿科济南250011

目的系统评价中国儿童及青少年遗尿症患病率。方法计算机检索CNKI、WanFang Data、VIP、SinoMed、PubMed、Embase、Web of Science数据库,搜集关于中国儿童及青少年遗尿症患病率的横断面研究,检索时限均从建库至2023年11月。由2名评价... 详细信息

目的系统评价中国儿童及青少年遗尿症患病率。方法计算机检索CNKI、WanFang Data、VIP、SinoMed、PubMed、Embase、Web of Science数据库,搜集关于中国儿童及青少年遗尿症患病率的横断面研究,检索时限均从建库至2023年11月。由2名评价员独立筛选文献、提取数据并评价纳入研究的偏倚风险后,应用R软件进行Meta分析,采用baujat图、亚组分析探讨异质性来源,采用逐一剔除法进行敏感性分析。结果共纳入38篇文献,包括327065例研究对象,其中遗尿症患儿18392名,合并患病率为5.59%[95%CI(4.58%,6.81%)]。遗尿症患病率随年龄升高呈明显下降趋势,5岁、12岁、18岁患病率分别为12.30%[95%CI(9.96%,15.11%)]、2.07%[95%CI(1.68%,2.56%)]和1.95%[95%CI(0.90%,4.20%)]。男童患病率6.36%[95%CI(5.49%,7.36%)]高于女童4.30%[95%CI(3.57%,5.16%)]。使用DSM-IV为诊断标准的患病率为3.78%[95%CI(2.58%,5.52%)],以ICCS为诊断标准的患病率为5.99%[95%CI(4.75%,7.52%)]。结论中国儿童及青少年遗尿症患病率受地区、年龄、性别、诊断标准的影响,华南地区患病率更高,患病率随年龄升高而降低,男性患病率高于女性。

关键词：遗尿症患病率 Meta分析儿童青少年

一种基于55 nm CMOS工艺的V波段高功率宽带功率放大器

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微电子学 2024年第3期54卷 369-374页

作者：肖晗姜浩然王研陈强桑磊合肥工业大学微电子学院合肥230002 中国电子科技集团公司第三十八研究所合肥230031

基于标准55 nm CMOS工艺设计了一款工作在V波段下的高输出功率宽带功率放大器,放大器采用交叉中和电容技术来提高功率放大器的增益和稳定性,并通过两路功率合成网络提高输出功率。通过多频点叠加技术设计级间变压器,拓展放大器带宽。仿... 详细信息

基于标准55 nm CMOS工艺设计了一款工作在V波段下的高输出功率宽带功率放大器,放大器采用交叉中和电容技术来提高功率放大器的增益和稳定性,并通过两路功率合成网络提高输出功率。通过多频点叠加技术设计级间变压器,拓展放大器带宽。仿真结果表明,在1.2 V电源电压下,放大器的3 dB带宽为14.5 GHz,静态直流功耗为184 mW,饱和输出功率为13.2 dBm,小信号增益为16.6 dB,具有高宽带、高输出功率的优点。

关键词：功率放大器 CMOS 毫米波集成电路高功率宽带

不同补片固定方式在腹股沟疝腹腔镜完全腹膜外疝修补术中的应用价值探讨

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外科研究与新技术（中英文） 2024年第3期13卷 227-230页

作者：刘小宇姜浩然北京市平谷区中医医院外科北京101200

目的探讨不同补片固定方式在腹股沟疝腹腔镜完全腹膜外(TEP)疝修补术中的应用价值。方法选取2020年3月—2023年3月北京市平谷区中医医院收治的100例腹股沟疝患者,按照治疗方式的不同分为免固定组(67例,采用自固定补片进行腹腔镜TEP疝修... 详细信息

目的探讨不同补片固定方式在腹股沟疝腹腔镜完全腹膜外(TEP)疝修补术中的应用价值。方法选取2020年3月—2023年3月北京市平谷区中医医院收治的100例腹股沟疝患者,按照治疗方式的不同分为免固定组(67例,采用自固定补片进行腹腔镜TEP疝修补术)和医用胶组(33例,采用传统补片进行腹腔镜TEP疝修补术);对两组患者临床资料进行比较分析。结果两组手术时间及术中出血量比较,差异无统计学意义(P>0.05),免固定组肛门首次排气时间、术后进食时间、自主活动时间及住院时间均显著短于医用胶组(P<0.05);经治疗,两组患者视觉模拟评分法(VAS)评分、健康调查量表36(SF-36)评分均得到显著改善(P<0.05),且免固定组治疗后各时间点VAS评分及术后6个月SF-36评分均显著优于医用胶组(P<0.05);免固定组术后并发症发生率显著低于医用胶组(P<0.05)。结论采用自固定补片腹腔镜TEP疝修补术治疗腹股沟疝可促进患者术后康复,同时显著降低术后并发症,值得临床借鉴推广。

关键词：腹股沟疝腹腔镜完全腹膜外疝修补术自固定补片生活质量

A Li-S battery with ultrahigh cycling stability and enhanced rate capability based on novel ZnO yolk-shell sulfur host

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Journal of Energy Chemistry 2021年第4期30卷 136-144页

作者： Ruihan Zhang Maochun Wu Xinzhuang Fan haoran jiang Tianshou Zhao Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Currently,lithium-sulfur(Li-S)batteries still suffer from fast capacity decay,poor coulombic efficiency(CE)and short cycling lifespan,which result from the severe shuttle effect issue caused by high solubility and rapid diffusion of lithium polysulfides(Li PSs)in organic ***,yolk-shell zinc oxide(YSZn O)spheres are synthesized and for the first time,applied as a host for Li-S batteries to tackle this *** polar Zn O exhibits high chemical anchoring ability toward Li PSs while the unique yolk-shell structure not only provides an additional physical barrier to Li PSs but also enables much more uniform sulfur distribution,thus significantly suppressing Li PSs shuttling effect meanwhile promoting sulfur conversion *** a result,the YS-Zn O enables the Li-S battery to display an initial specific capacity of1355 m Ah g^(-1) and an outstanding capacity retention capability(~89.44%retention rate)even after 500 cycles with the average CE of~99.46%at the current of 0.5 *** contrast,the capacity of conventional-Zn O-nanoparticles based battery severely decays to 472 m Ah g^(-1) after cycling for 500 *** impressively,the S/YS-Zn O based Li-S battery can maintain a low decay rate of 0.040%every cycle and high average CE of 98.82%over 1000 cycles at 3 C.

关键词： Yolk-shell structure Lithium-sulfur batteries Zinc oxide Shuttle effect In-situ Raman test

Ab initio prediction and characterization of phosphorene-like SiS and SiSe as anode materials for sodium-ion batteries

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Science Bulletin 2017年第8期62卷 572-578页

作者： haoran jiang Tianshou Zhao Yuxun Ren Ruihan Zhang Maochun Wu Department of Mechanicol and Aerospace Engineering The Hong Kong University of Science and Technology Hong Kong. Chino

In this work, a density functional theory （DFT） based first-principles study is carried out to investigate tile potential of phosphorene-like SiS and SiSe monolayers as anode materials for sodium-ion （Na-ion） bat- teries. Results show that both SiS and SiSe have large adsorption energies towards single Na atom of 0.94 and -0.43 eV, owing to the charge transfers from Na to SiS or SiSe. In addition, it is found that the highest Na concentration for both SiS and SiSe is x = 1 with the chemical formulas of NaSiS and NaSiSe, corresponding to the high theoretical specific capacities for Na storages of 445.6 and 250.4 mAh g 1, respectively. Moreover, Na diffusions are very fast and show strong directional behaviors on SiS and SiSe monolayers, with the energy barriers of only 0.135 and 0.158 eV, lower than those of con- ventional anode materials for Na-ion batteries such as Na2Ti3O7 （0.19 eV） and Na3Sb （0.21 eV）. Finally, although SiS and SiSe show semiconducting behaviors, they transform to metallic states after adsorbing Na atoms, indicating enhanced electrical conductivity during battery cycling. Given these advantages, it is expected that both SiS and SiSe monolayers are promising anode materials for Na-ion batteries, and in principle, other Na-based batteries as well.

关键词： Na-ion batteries Phosphorene-like SiS SiSe First-principles study Anode materials

Image recognition and empirical application of desert plant species based on convolutional neural network

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Journal of Arid Land 2022年第12期14卷 1440-1455页

作者： LI Jicai SUN Shiding jiang haoran TIAN Yingjie XU Xiaoliang School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of SciencesBeijing 100190China Research Center on Fictitious Economy and Data Science Chinese Academy of SciencesBeijing 100190China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

In recent years,deep convolution neural network has exhibited excellent performance in computer vision and has a far-reaching *** plant taxonomic identification requires high expertise,which is *** nature reserves have problems such as incomplete species surveys,inaccurate taxonomic identification,and untimely updating of status *** and accurate recognition of plant images can be achieved by applying convolutional neural network technology to explore the best network *** 24 typical desert plant species that are widely distributed in the nature reserves in Xinjiang Uygur Autonomous Region of China as the research objects,this study established an image database and select the optimal network model for the image recognition of desert plant species to provide decision support for fine management in the nature reserves in Xinjiang,such as species investigation and monitoring,by using deep *** desert plant species were not included in the public dataset,the images used in this study were mainly obtained through field shooting and downloaded from the Plant Photo Bank of China(PPBC).After the sorting process and statistical analysis,a total of 2331 plant images were finally collected(2071 images from field collection and 260 images from the PPBC),including 24 plant species belonging to 14 families and 22 genera.A large number of numerical experiments were also carried out to compare a series of 37 convolutional neural network models with good performance,from different perspectives,to find the optimal network model that is most suitable for the image recognition of desert plant species in *** results revealed 24 models with a recognition Accuracy,of greater than 70.000%.Among which,Residual Network X_8GF(RegNetX_8GF)performs the best,with Accuracy,Precision,Recall,and F1(which refers to the harmonic mean of the Precision and Recall values)values of 78.33%,77.65%,69.55%,and 71.26%,*** t

关键词： desert plants image recognition deep learning convolutional neural network Residual Network X_8GF(RegNetX_8GF) Mobile Network V2(MobileNetV2) nature reserves