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Performance Assessment and Improvement of Photovoltaic-Thermal System based on Energy,Exergy,Economic and Environment Analysis

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Journal of Thermal Science 2024年第06期33卷 2166-2178页

作者： ZHOU Yuan WANG Jiangjiang qin Yanbo LIU Boxiang Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology North China Electric Power University

A photovoltaic thermal（PV/T） system with parallel cooling channels was designed in this work to decrease the PV panel temperature and improve its photoelectric conversion efficiency.A 4E analysis method（includes energy,exergy,economic,and environmental aspects） was formulated to comprehensively evaluate the performances of the PV/T system,combining experimental and simulation ***,the experiment was performed using water as the cooling *** show that the PV/T system can reduce daily CO2emissions by 1682.47-1705.98 g,and compared to the PV system,the added cooling module can increase electrical efficiency and environmental performance by 12.19% and 6.2%,*** the mass flow of water rose from 0.017 kg/s to 0.023 kg/s,the electrical,thermal,and overall efficiencies were improved by 3.82%,11.36%,and 8.27%,***,a numerical simulation model was constructed based on the experimental results to predict operations of the presented PV/T system using nanofluids as the cooling medium,including Ag,Al2O3,and *** results show that the Al2O3-nanofluid-based PV/T system has a higher application value,enabling an electrical efficiency of up to 15.13%.Its thermal efficiency can be enhanced by5.43% when the volume fraction of Al2O3increases from 1% to 5%.

关键词： 4E analysis method nanofluid numerical analysis parallel cooling channels photovoltaic/thermal system

三氧化矿物凝聚体牙髓切断术治疗年轻恒牙不可复性牙髓炎的初步研究

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中华口腔医学杂志 2015年第12期50卷 715-719页

作者：彭楚芳赵玉鸣杨媛秦满北京大学口腔医学院·口腔医院儿童口腔科 100081

目的评估三氧化矿物凝聚体（mineral trioxide aggragate,MTA）牙髓切断术治疗年轻恒牙不可复性牙髓炎的临床效果,为年轻恒牙不可复性牙髓炎的治疗提供新思路.方法选取北京大学口腔医学院·口腔医院儿童口腔科就诊的26例患者,对其临... 详细信息

目的评估三氧化矿物凝聚体（mineral trioxide aggragate,MTA）牙髓切断术治疗年轻恒牙不可复性牙髓炎的临床效果,为年轻恒牙不可复性牙髓炎的治疗提供新思路.方法选取北京大学口腔医学院·口腔医院儿童口腔科就诊的26例患者,对其临床诊断为不可复性牙髓炎的26颗年轻恒牙应用MTA作为盖髓剂,根据切断牙髓部位的出血情况行部分或全部冠髓切断,术后1年随访,通过临床和X线片检查评估治疗效果.结果术后1年,4例患者失访,其他22例患者（共计22颗患牙）进行了复查.22颗牙中20颗牙判为治愈或有效,临床成功率为91％（20/22）;13颗牙在X线片上可见钙化桥,钙化桥形成率为65％（13/20）.结论 MTA牙髓切断术是治疗年轻恒牙不可复性牙髓炎的有效方法,但长期疗效还需进一步观察.

关键词：牙髓炎牙髓切断术年轻恒牙三氧化矿物凝聚体

循环Alarin在肥胖儿童中的水平及与胰岛素抵抗的相关性

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中国当代儿科杂志 2019年第10期21卷 983-986页

作者：李曼琴李骄阳谢丽南华大学附属第一医院儿科重症监护室湖南衡阳421001 南华大学附属第一医院内分泌科湖南衡阳421001

目的本研究拟探讨循环Alarin在肥胖儿童中的表达水平及与代谢参数的关系。方法招募体重指数(BMI)高于第95百分位数的肥胖儿童86例为肥胖组,82例年龄和性别与肥胖组匹配的BMI低于第85百分位数的健康儿童作为健康对照组。根据是否发生胰... 详细信息

目的本研究拟探讨循环Alarin在肥胖儿童中的表达水平及与代谢参数的关系。方法招募体重指数(BMI)高于第95百分位数的肥胖儿童86例为肥胖组,82例年龄和性别与肥胖组匹配的BMI低于第85百分位数的健康儿童作为健康对照组。根据是否发生胰岛素抵抗(IR),将86例肥胖组儿童分为IR组(n=27)和非IR组(n=59)。测量身高、体重、收缩压(SBP)和舒张压(SDP),并计算体重指数(BMI)。检测总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、尿酸(UA)、空腹胰岛素(FINS)及空腹血糖(FBG)水平,并计算葡萄糖和胰岛素曲线下面积(AUC)、稳态模型胰岛素抵抗指数(HOMA-IR)、全身胰岛素敏感性指标(WBISI)。ELISA法检测循环Alarin水平。结果肥胖组儿童循环Alarin水平较健康对照组显著升高,IR组儿童循环Alarin水平较非IR组显著升高(P < 0.01)。循环Alarin与BMI、TG、FBG、AUC葡萄糖、AUC胰岛素、HOMA-IR呈正相关,与WBISI呈负相关(P < 0.05)。循环Alarin的变化与BMI、FBG、HOMA-IR有线性回归关系,其中HOMA-IR对循环Alarin的影响最大(P < 0.05)。结论循环Alarin水平在肥胖儿童中显著升高,可能与肥胖和IR的发生有关。

关键词：肥胖 Alarin 胰岛素抵抗儿童

Construction of Optimal Mixed-Level Uniform Designs

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Journal of Systems Science & Complexity 2024年第2期37卷 841-862页

作者： CHATTERJEE Kashinath LIU Min-Qian qin Hong YANG Liuqing Department of Population Health Sciences Division of Biostatistics and Data ScienceAugusta UniversityGA 30912USA NITFID LPMC&KLMDASRSchool of Statistics and Data ScienceNankai UniversityTianjin 300071China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China

The theory of uniform design has received increasing interest because of its wide application in the field of computer *** generalized discrete discrepancy is proposed to evaluate the uniformity of the mixed-level factorial *** this paper,the authors give a lower bound of the generalized discrete discrepancy and provide some construction methods of optimal mixed-level uniform designs which can achieve this lower *** methods are all deterministic construction methods which can avoid the complexity of stochastic *** saturated mixed-level uniform designs and supersaturated mixed-level uniform designs can be obtained with these ***,the resulting designs are also χ^(2)-optimal and minimum moment aberration designs.

关键词： Generalized discrete discrepancy Hadamard matrix mixed-level design orthogonal array supersaturated design

Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble

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Nuclear Science and Techniques 2024年第3期35卷 216-227页

作者： Deng Liu Alam Noor A Zhen-Zhen qin Yang Lei School of Mathematics and Physics Southwest University of Science and TechnologyMianyang 621010China School of Nuclear Science and Technology Southwest University of Science and TechnologyMianyang 621010China

The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output *** quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the ***,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists.

关键词： Neural network Two-body random ensemble Spin distribution of nuclear ground state

A review on the multi-scaled structures and mechanical/thermal properties of tool steels fabricated by laser powder bed fusion additive manufacturing

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1048-1071页

作者： Huajing Zong Nan Kang Zehao qin Mohamed El mansori Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege Station TX77843USA

The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds *** appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in ***,LPBF-processed tool steels have attracted more and more *** complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool *** paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal *** microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to ***,a summary of tool steels and their challenges and outlooks are introduced.

关键词： additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties

Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures

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International Journal of Extreme manufacturing 2024年第1期6卷 328-338页

作者： Qiang Liu Wei Xu Xiaoxi Li Tongyao Zhang Chengbing qin Fang Luo Zhihong Zhu Shiqiao qin Mengjian Zhu Kostya S Novoselov College of Advanced Interdisciplinary Studies&Hunan Provincial Key Laboratory of Novel Nano-optoelectronic Information Materials and Devices National University of Defense TechnologyChangshaHunan 410073People’s Republic of China Nanhu Laser Laboratory National University of Defense TechnologyChangshaHunan 410073People’s Republic of China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006People’s Republic of China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006People’s Republic of China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006People’s Republic of China Institute for Functional Intelligent Materials National University of SingaporeSingapore 117544Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and *** record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter which can be further integrated into arbitrary platforms by van der Waals ***,due to the zero bandgap,graphene is difficult to emit light through the interband recombination of carriers like conventional ***,we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride(Gr/hBN)*** in biased graphene are significantly heated up to 2800 K at modest electric fields,emitting bright photons from the near-infrared to the visible spectral *** eliminating the heat dissipation channel of the substrate,the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on SiO2or *** demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal *** cooling ofhigh-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface,resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical *** is found thatsuspending the Gr/hBN heterostructures on the SiO2trenches significantly modifies the light emission due to the formation of the optical cavity and showed a~440%enhancement inintensity at the peak wavelength of 940 nm compared to the black-body thermal *** demonstration of electrically driven ultrafast light emission from suspended Gr/hBNheterostructures sheds the light on applications of graphene heterostructures in photonicintegrated circuits,such as broadband light sources and ultrafast thermo-optic phase modulat

关键词： suspended graphene ultrafast light emitter van der Waals heterostructures thermal radiation electron–phonon interaction

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1株人源抑制致病菌的粪肠球菌性能评价

中国抗生素杂志 2022年第7期47卷 703-710页

作者：唐乐邓淑芬秦嫚嫚江友裘梁江西中医药大学医学转化中心南昌330006 江西中医药大学江西省中药防治血管重塑相关疾病重点实验室南昌330006 深圳市宝安区石岩人民医院深圳518108

目的对分离自健康成人粪便中的一株粪肠球菌QT01进行生物学性质和抑制致病菌能力评价。方法采用PCR方法扩增16S rDNA基因并测序确定分离菌株的种属;采用药敏试验和耐酸耐胆盐试验评价QT01对抗生素敏感性及耐受胃肠道能力;采用抑制试验评... 详细信息

目的对分离自健康成人粪便中的一株粪肠球菌QT01进行生物学性质和抑制致病菌能力评价。方法采用PCR方法扩增16S rDNA基因并测序确定分离菌株的种属;采用药敏试验和耐酸耐胆盐试验评价QT01对抗生素敏感性及耐受胃肠道能力;采用抑制试验评价QT01拮抗致病菌和益生菌的能力。结果经16S rDNA序列同源性分析,鉴定该菌株为粪肠球菌(Enterococcus faecalis);它不耐酸,但具有较强的耐胆盐能力;对常见抗生素如阿莫西林、青霉素、氯霉素和环丙沙星等敏感;能抑制粪肠球菌致病株V583和产气肠杆菌,但不能抑制植物乳杆菌和嗜热链球菌。结论粪肠球菌QT01不耐酸耐胆盐,对抗生素敏感,能够抑制致病菌V583,在微生态制剂产品开发方面具有应用潜力。

关键词：粪便粪肠球菌抑菌益生性

Anti-asthmatic activity of alkaloid compounds from Pericarpium Citri Reticulatae（Citrus reticulata ’Chachi’）

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Anti-asthmatic activity of alkaloid compounds from Pericarpi...