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Interview with Professor Jianhua Zhang,Editor‑in‑Chief of Moore and More
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作者 Lin Jiang Yi Li jianhua zhang 《Moore and More》 2024年第1期248-250,共3页
Here we are honored to have an interview with the Editorin-Chief of Moore and More,Prof.Jianhua Zhang,about the journal’s scope and aspirations for the future.Prof.Zhang is also the executive dean of the School of Mi... Here we are honored to have an interview with the Editorin-Chief of Moore and More,Prof.Jianhua Zhang,about the journal’s scope and aspirations for the future.Prof.Zhang is also the executive dean of the School of Microelectronics at Shanghai University in Shanghai,China.Meanwhile,she serves concurrently as the President of Society for Information Display(SID)Beijing Chapter of the International,an executive director of the Robotics Branch of the Chinese Mechanical Engineering Society,a director of the Tribology Branch of the Chinese Mechanical Engineering Society,a director of the Micro nano Manufacturing Technology Branch of the Chinese Mechanical Engineering Society,a director of the Luminescence Branch of the Chinese Physical Society. 展开更多
关键词 editor chief journal scope Shanghai University director tribol future ASPIRATIONS MICROELECTRONICS Moore More
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Minimizing tin(Ⅱ) oxidation using ethylhydrazine oxalate for high-performance all-perovskite tandem solar cells 被引量:1
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作者 jianhua zhang Xufeng Liao +9 位作者 Weisheng Li Yutian Tian Qinyang Huang Yitong Ji Guotang Hu Qingguo Du Wenchao Huang Donghoe Kim Yi-Bing Cheng Jinhui Tong 《Journal of Semiconductors》 2025年第5期88-94,共7页
All-perovskite tandem solar cells(ATSCs) have the potential to surpass the Shockley-Queisser efficiency limit of conventional single-junction devices. However, the performance and stability of mixed tin–lead(Sn–Pb) ... All-perovskite tandem solar cells(ATSCs) have the potential to surpass the Shockley-Queisser efficiency limit of conventional single-junction devices. However, the performance and stability of mixed tin–lead(Sn–Pb) perovskite solar cells(PSCs), which are crucial components of ATSCs, are much lower than those of lead-based perovskites. The primary challenges include the high crystallization rate of perovskite materials and the susceptibility of Sn^(2+) oxidation, which leads to rough morphology and unfavorable p-type self-doping. To address these issues, we introduced ethylhydrazine oxalate(EDO) at the perovskite interface, which effectively inhibits the oxidation of Sn^(2+) and simultaneously enhances the crystallinity of the perovskite. Consequently, the EDO-modified mixed tin-lead PSCs reached a power conversion efficiency(PCE) of 21.96% with high reproducibility. We further achieved a 27.58% efficient ATSCs by using EDO as interfacial passivator in the Sn-Pb PSCs. 展开更多
关键词 mixed tin–lead perovskite solar cells ethylhydrazine oxalate Sn^(2+)oxidation all-perovskite tandem solar cells
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Post-anthesis dry matter production and leaf nitrogen distribution are associated with root-derived cytokinins gradient in rice
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作者 Kuanyu Zhu Yuemei Xu +9 位作者 Zhiwei Sun Yajun zhang Weiyang zhang Yunji Xu Junfei Gu Hao zhang Zhiqin Wang Lijun Liu jianhua zhang Jianchang Yang 《Journal of Integrative Agriculture》 2025年第6期2106-2122,共17页
Aligning leaf nitrogen(N) distribution to match the light gradient is crucial for maximizing canopy dry matter production(DMP) and improving N utilization efficiency. However, the relationship between the gradient of ... Aligning leaf nitrogen(N) distribution to match the light gradient is crucial for maximizing canopy dry matter production(DMP) and improving N utilization efficiency. However, the relationship between the gradient of root-derived cytokinins and N distribution in rice leaves and its impact on DMP and the underlying mechanisms remains poorly understood. A two-year field experiment was conducted using two japonica N-efficient varieties(NEVs) and two japonica N-inefficient varieties(NIVs) under four different N rates(0, 90, 180, and 360 kg N ha^(-1)). These selected varieties exhibited similar values in the coefficient of light extinction(K_(L)). Results showed that at lower N rates(0–180 kg N ha^(-1)), the NEVs exhibited greater dry matter weight at maturity, higher grain yield, and improved internal N use efficiency(IE_(N)) compared to the NIVs, despite possessing comparable total N uptake. Compared with the NIVs, the NEVs exhibited a more pronounced nitrogen distribution gradient in leaves, as indicated by the coefficient of nitrogen extinction(K_(N)) values during the middle and early grain-filling stages. This enhanced gradient led to improved coordination between light and nitrogen, resulting in greater photosynthetic production, particularly at lower N rates. Furthermore, the NEVs demonstrated a larger gradient of zeatin(Z)+zeatin riboside(ZR) in leaves(i.e., higher ratios of Z+ZR levels between upper and lower leaves), enhanced expression levels of genes related to N export in lower leaves and Z+ZR loading in the root, respectively, elevated enzymes activities related to N assimilation in upper leaves, in relative to the NIVs. Correlation and random forest analyses demonstrated a strong positive correlation between the Z+ZR gradient, K_(N), and DMP, and the gradient facilitated the export of N from lower leaves and its assimilation in upper leaves, contributing significantly to both K_(N) and DMP. This process was closely linked to root activity, including root oxidation activity, root Z+ZR content, and Z+ZR loading capacity, as confirmed by applying an inhibitor or a promoter of cytokinins biosynthesis to roots. Interestingly, at the N rate of 360 kg N ha^(-1), both NEVs and NIVs showed indistinguishable plant traits, achieving a super high-yielding level(over 10.5 t ha^(-1)) but with remarkably low IE_(N). The results suggest that increasing the Z+ZR gradient can improve K_(N) and DMP, where it needs to maintain higher root activity, thus leading to high yield and high IE_(N). Further research is needed to explore and develop cultivation practices with reduced N to unlock the super-high-yielding potential of the NEVs. 展开更多
关键词 rice(Oryza sativa L.) grain yield dry matter production cytokinins gradient N distribution internal N use efficiency
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ABA biosynthesis rather than ABA catabolism is induced by low temperature and inhibits seed germination by activating OsTPP3
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作者 Zhonge Qin Jiahan Lyu +6 位作者 Zhenning Teng Shuang Meng Yan Peng Dingyang Yuan Meijuan Duan jianhua zhang Nenghui Ye 《The Crop Journal》 2025年第3期752-763,共12页
Low-temperature(LT)stress is a significant abiotic stress in rice growth,especially under direct seeding cultivation,where low temperatures can significantly affect seed germination and seedling growth of direct-seede... Low-temperature(LT)stress is a significant abiotic stress in rice growth,especially under direct seeding cultivation,where low temperatures can significantly affect seed germination and seedling growth of direct-seeded rice,thereby impacting the final yield of rice.In this study,we have identified a trehalose synthesis pathway gene,trehalose-6-phosphate phosphatase 3(Os TPP3),involved in the regulation of low-temperature(LT)germination in rice,as well as its upstream regulatory factor,the ABA signaling pathway gene OsbZIP23.LT stress induced the accumulation of ABA by upregulating the expression of Os NCED3.Consistently,the overexpression of Os NCED3 significantly inhibited seed germination under LT.RT-q PCR experiments found that the expression of OsbZIP23 was also significantly induced under LT stress and ABA treatment.Overexpression of OsbZIP23 has increased the sensitivity to LT stress of rice seed,resembling the phenotype of Os NCED3 overexpressing seeds.Furthermore,both LT stress and exogenous ABA treatment increased the trehalose content in WT seeds by upregulating the expression of Os TPP3.Enhancing the expression of Os TPP3 or application of exogenous trehalose have significantly increased the sensitivity to LT stress during seed germination.Transcriptional activation and yeast one-hybrid assays demonstrated that OsbZIP23 bound to the promoter of Os TPP3 and activated its expression,which was intensified by LT stress or the application of ABA.Our study discovered an ABAdependent OsbZIP23–Os TPP3 module that responds to LT stress,inhibiting seed germination under LT conditions by increasing trehalose accumulation,thus might balance the growth and stress resistance and provide a new insight into the genetic improvement of rice cultivars with better LT germination performance. 展开更多
关键词 Seed germination Abscisic acid TREHALOSE Osbzip23 Low-temperature stress Ostpp3
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Multifunctional polyimide performance prediction based on explainable machine learning
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作者 Suisui Wang Tianyong zhang +6 位作者 Han zhang Wenxuan Zhu Zixu Gu Xufeng Huang Hande zhang Bin Li jianhua zhang 《Smart Molecules》 2025年第4期92-102,共11页
Polyimides(PIs)are widely used in the microelectronics field due to their excellent comprehensive performance and the diversity and designability of their structures.In flexible substrate applications,designing the mo... Polyimides(PIs)are widely used in the microelectronics field due to their excellent comprehensive performance and the diversity and designability of their structures.In flexible substrate applications,designing the molecular structure to balance thermodynamic and optical properties is the most critical part of the PI design process.To accelerate the discovery of high-performance PIs,we established predictive models for glass transition temperature(T_(g)),cut-off wavelength(CW),and coefficient of thermal expansion(CTE)using various machine learning algorithms.The optimal predictive models for the three properties demonstrated high accuracy and stability in both test set predictions and cross-validation results.Additionally,the interpretability of the three optimal models was analyzed using the SHAP method,and the accuracy and generalization ability of the models were validated using several novel PIs.By combining the three models,predictions were made for multiple PIs,leading to the selection and synthesis of PIs with excellent comprehensive performance.135 novel PIs were designed and their key properties were obtained without the need for experimental verification.The predictive models established in this study can assist researchers in quickly determining the T_(g),CW and CTE of PIs,thereby facilitating the swift identification of promising candidates for further development. 展开更多
关键词 cut-off wavelength machine learning performance prediction polyimides THERMODYNAMICS
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Network pharmacology and molecular docking reveal the potential inner mechanism between sensitive skin and hyperpigmentation
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作者 jianhua zhang Shichao Liu +2 位作者 Wenjiao Guo Zhiyun Du Li Lin 《Journal of Dermatologic Science and Cosmetic Technology》 2025年第1期11-23,共13页
Background:Sensitive skin affects a substantial portion of the global population and has significant implications for skin health and well-being.In addition to unpleasant sensory effects,individuals with sensitive ski... Background:Sensitive skin affects a substantial portion of the global population and has significant implications for skin health and well-being.In addition to unpleasant sensory effects,individuals with sensitive skin were likely to be more susceptible to hyperpigmentation.However,the association between sensitive skin and hyperpigmentation,as well as the underlying molecular mechanisms,remain unclear.Objective:This study aims to investigate the correlation and intrinsic mechanisms between sensitive skin and hyperpigmentation through network pharmacology combined with molecular docking.Materials and Methods:The targets associated with sensitive skin and hyperpigmentation were collected from the human gene database,GeneCards.Subsequently,the protein-protein interaction(PPI)network,Kyoto Encyclopedia of Genes and Genomes(KEGG),and Gene Ontology(GO)enrichment analysis were performed to explore the biological connections between sensitive skin and hyperpigmentation.Additionally,the targets of 15 active compounds with reported lightening effects were collected from TCMSP,BATMAN and SymMap databases.Target analysis and molecular docking were performed to identify potential candidates for addressing hyperpigmentation on sensitive skin.The anti-melanogenesis effect of the identified candidate was verified in B16F10 cells.Results:A total of 16971 sensitive skin targets and 11382 hyperpigmentation targets were screened,and 9693 overlapping targets were identified,with a core set comprising 164 targets.The combination of PPI network,KEGG and GO analysis revealed the key role of tyrosinase and immune-mediated inflammation in pigmentation on sensitive skin.Among the 15 active compounds,oxyresveratrol was identified as having a high correlation with the core set targets and predicted strong inhibition of Tyrosine-protein Kinase Kit.The application of oxyresveratrol exhibited a dose-dependent suppression of melanin production in B16F10 cells.Conclusion:This study suggested the crucial roles of immune-mediated inflammation in sensitive skin and hyperpigmentation,as well as highlighted the potential of oxyresveratrol in addressing hyperpigmentation on sensitive skin.These comprehensive findings provide a deeper understanding of the connection mechanism between sensitive skin and hyperpigmentation,offering new insights for the development of targeted treatments and interventions. 展开更多
关键词 Sensitive skin HYPERPIGMENTATION OXYRESVERATROL Network pharmacology Molecular docking
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Dynamic hybrid visual-thermal multimodal perception neuromorphic devices based on defect modulation of electrospun nanofibers
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作者 Shengkai Wen Yanan Liu +3 位作者 Yi Li Liang Xie Jun Li jianhua zhang 《International Journal of Extreme Manufacturing》 2025年第2期749-761,共13页
Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mo... Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mode of external information acquisition in living organisms,has garnered substantial scholarly interest.Notwithstanding numerous studies simulating the retina through optical synapses,their applications remain circumscribed to single-mode perception.Moreover,the pivotal role of temperature,a fundamental regulator of biological activities,has regrettably been relegated to the periphery.To address these limitations,we proffer a neuromorphic device endowed with multimodal perception,grounded in the principles of light-modulated semiconductors.This device seamlessly accomplishes dynamic hybrid visual and thermal multimodal perception,featuring temperature-dependent paired pulse facilitation properties and adaptive storage.Crucially,our meticulous examination of transfer curves,capacitance–voltage(C–V)tests,and noise measurements provides insights into interface and bulk defects,elucidating the physical mechanisms underlying adaptive storage and other functionalities.Additionally,the device demonstrates a variety of synaptic functionalities,including filtering properties,Ebbinghaus curves,and memory applications in image recognition.Surprisingly,the digital recognition rate achieves a remarkable value of 98.8%. 展开更多
关键词 neuromorphic devices electrospinning defect modulation dynamic hybrid multimodal perception adaptive storage
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Applications of Carbon-Based Multivariable Chemical Sensors for Analyte Recognition
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作者 Lin Shi Jian Song +5 位作者 Yu Wang Heng Fu Kingsley Patrick-Iwuanyanwu Lei zhang Charles H.Lawrie jianhua zhang 《Nano-Micro Letters》 2025年第10期417-452,共36页
Over recent decades,carbon-based chemical sensor technologies have advanced significantly.Nevertheless,significant opportunities persist for enhancing analyte recognition capabilities,particularly in complex environme... Over recent decades,carbon-based chemical sensor technologies have advanced significantly.Nevertheless,significant opportunities persist for enhancing analyte recognition capabilities,particularly in complex environments.Conventional monovariable sensors exhibit inherent limitations,such as susceptibility to interference from coexisting analytes,which results in response overlap.Although sensor arrays,through modification of multiple sensing materials,offer a potential solution for analyte recognition,their practical applications are constrained by intricate material modification processes.In this context,multivariable chemical sensors have emerged as a promising alternative,enabling the generation of multiple outputs to construct a comprehensive sensing space for analyte recognition,while utilizing a single sensing material.Among various carbon-based materials,carbon nanotubes(CNTs)and graphene have emerged as ideal candidates for constructing high-performance chemical sensors,owing to their well-established batch fabrication processes,superior electrical properties,and outstanding sensing capabilities.This review examines the progress of carbon-based multivariable chemical sensors,focusing on CNTs/graphene as sensing materials and field-effect transistors as transducers for analyte recognition.The discussion encompasses fundamental aspects of these sensors,including sensing materials,sensor architectures,performance metrics,pattern recognition algorithms,and multivariable sensing mechanism.Furthermore,the review highlights innovative multivariable extraction schemes and their practical applications when integrated with advanced pattern recognition algorithms. 展开更多
关键词 Carbon nanotubes GRAPHENE Field-effect transistors Gas sensors Biosensors
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Analysis of the Efficacy of High-Flow Nasal Cannula Oxygen Therapy and Non-Invasive Ventilation in COPD Patients
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作者 Xue Yin Yan Li +6 位作者 Yan Ma Yue Sun Li Li Wenmei Yan jianhua zhang He zhang Haisheng Yang 《Journal of Clinical and Nursing Research》 2025年第11期307-315,共9页
Patients with acute exacerbation of chronic obstructive pulmonary disease(COPD)often suffer from respiratory failure and require respiratory support therapy.High-flow nasal cannula oxygen therapy(HFNC)and non-invasive... Patients with acute exacerbation of chronic obstructive pulmonary disease(COPD)often suffer from respiratory failure and require respiratory support therapy.High-flow nasal cannula oxygen therapy(HFNC)and non-invasive positive pressure ventilation(NIPPV)are commonly used non-invasive respiratory support methods.HFNC can provide precisely heated and humidified high-flow oxygen,reducing dead space and increasing alveolar ventilation.NIPPV can supply stable high-concentration oxygen and improve gas exchange.This article reviews the application of HFNC and NIPPV in the acute exacerbation stage of COPD,aiming to provide references for reasonable clinical selection. 展开更多
关键词 Chronic obstructive pulmonary disease High-flow nasal cannula oxygen therapy Non-invasive ventilation Acute exacerbation stage
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Recent advances in Prussian blue analogues as cathode materials for sodium-ion batteries
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作者 Bofeng zhang jianhua zhang +2 位作者 Yingxue He Kailing Zhou Hao Wang 《Journal of Energy Chemistry》 2025年第11期593-613,I0015,共22页
Prussian blue analogues(PBAs)have emerged as highly promising cathode materials for sodium-ion batteries(SIBs)due to their simple synthesis,low cost,structural tunability,and high theoretical capacity.However,despite ... Prussian blue analogues(PBAs)have emerged as highly promising cathode materials for sodium-ion batteries(SIBs)due to their simple synthesis,low cost,structural tunability,and high theoretical capacity.However,despite their significant potential,practical applications of PBAs still face multiple performance limitations.This review provides a comprehensive examination of PBAs structures and their electrochemical reaction mechanisms,and systematically summarizes current synthesis methods and modification strategies,while offering forward-looking insights.Furthermore,from the perspective of industrialization,this review systematically analyzes the synthesis,modification,and core challenges of PBAs by comparatively evaluating the feasibility of different technological pathways based on multiple dimensions,including cost-effectiveness,process scalability,environmental impact,and supply chain security,with the aim of providing forward-looking guidance for bridging the critical gap from lab to market. 展开更多
关键词 Prussian blue analogues Sodium-ion batteries Synthesis techniques Modification strategies
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Research and experimental validation for 3GPP ISAC channel modeling standardization
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作者 Yuxiang zhang jianhua zhang +5 位作者 Jiwei zhang Yuanpeng Pei Yameng Liu Lei Tian Tao Jiang Guangyi Liu 《Digital Communications and Networks》 2025年第5期1601-1613,共13页
Integrated Sensing and Communication(ISAC)is considered a key technology in 6G networks.An accurate sensing channel model is crucial for the design and sensing performance evaluation of ISAC systems.The widely used Ge... Integrated Sensing and Communication(ISAC)is considered a key technology in 6G networks.An accurate sensing channel model is crucial for the design and sensing performance evaluation of ISAC systems.The widely used Geometry-Based Stochastic Model(GBSM),typically applied in standardized channel modeling,mainly focuses on the statistical fading characteristics of the channel.However,it fails to capture the characteristics of targets in ISAC systems,such as their positions and velocities,as well as the impact of the targets on the background.To address this issue,this paper proposes an Extended-GBSM(E-GBSM)sensing channel model that incorporates newly discovered channel characteristics into a unified modeling framework.In this framework,the sensing channel is divided into target and background channels.For the target channel,the model introduces a concatenated modeling approach,while for the background channel,a parameter called the power control factor is introduced to assess impact of the target on the background channel,making the modeling framework applicable to both mono-static and bi-static sensing modes.To validate the proposed model’s effectiveness,measurements of target and background channels are conducted across a wide range of indoor and outdoor scenarios,covering various sensing targets such as metal plates,reconfigurable intelligent surfaces,human bodies,unmanned aerial vehicles,and vehicles.The experimental results provide important theoretical support and empirical data for the standardization of ISAC channel modeling. 展开更多
关键词 ISAC Channel modeling 3GPP standardization Channel measurement
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Exploration of the Value of Extract of Wuwei Xiaodu Drink on Rabbit Model of Spinal Infection
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作者 Qing Wang Ying Zhan +3 位作者 jianhua zhang Zheng Song Xiuping Li Qiang zhang 《Journal of Clinical and Nursing Research》 2025年第2期1-6,共6页
Objective:To study the therapeutic effect of the Extract of Wuwei Xiaodu Drink on spinal infection and provide the scientific basis for clinical application.Methods:By establishing a rabbit model of spinal infection,t... Objective:To study the therapeutic effect of the Extract of Wuwei Xiaodu Drink on spinal infection and provide the scientific basis for clinical application.Methods:By establishing a rabbit model of spinal infection,this paper observed and analyzed the changes in body mass before and after the intervention and the comparison of inflammation-related factors and blood leukocyte counts among the three groups.Results:There was a significant difference in the changes in body mass of rabbits before and after intervention in the experimental group,control group and blank group(P<0.05);there was no statistically significant difference in calcitoninogen,C-reactive protein and routine blood leukocyte counts between the experimental group and the control group(P>0.05),and there was a statistically significant difference in calcitoninogen,C-reactive protein and routine blood leukocyte counts between the experimental group and the blank group(P<0.05).Conclusion:The Extract of Wuwei Xiaodu Drink can play a protective role by regulating the level of inflammatory factors in blood routine leukocyte count and reducing the inflammatory reaction in the spinal cord injury area. 展开更多
关键词 Extract of Wuwei Xiaodu Drink Spinal infection Rabbit model
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循证护理在急性心肌梗死后心律失常中的效果和对患者焦虑情绪影响体会 被引量:6
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作者 张建华 陈渺 +1 位作者 黄妙琴 劳素银 《心血管外科杂志(电子版)》 2019年第2期193-194,共2页
目的探讨循证护理方案对急性心肌梗死并心律失常患者的临床治疗效果和负面心理影响。方法将2018年4月-2019年4月在本院接受治疗的90例急性心肌梗死并心律失常患者,随机分为两组,每组45例,对照组给予常规护理方案,观察组给予患者循证护... 目的探讨循证护理方案对急性心肌梗死并心律失常患者的临床治疗效果和负面心理影响。方法将2018年4月-2019年4月在本院接受治疗的90例急性心肌梗死并心律失常患者,随机分为两组,每组45例,对照组给予常规护理方案,观察组给予患者循证护理措施,将两组心理状态及治疗有效率记录和对比。结果观察组抑郁自评表(32.21±1.51)分,焦虑自评表分(32.13±0.34)分均显著低于对照组(P<0.05);观察组患者治疗效果93.33%高于对照组75.56%,差异比较具统计学意义(P<0.05)。结论对急性心肌梗死并心律失常患者患者,给予循证护理措施,能够改善患者心理状态,提升患者临床疗效,具一定临床应用价值。 展开更多
关键词 循证护理 急性心肌梗死 心律失常 负面情绪 临床效果
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Implementation of Statistical Analysis to Determine Optimum Ultimate Pit
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作者 Tawum Juvert Mbah Haiwang Ye +1 位作者 jianhua zhang Mei Long 《Open Journal of Geology》 2020年第12期1262-1279,共18页
The ultimate pit may affect other aspects in the life of a mine such as economical, technical, environmental, and social aspects. What makes it even more complex is that most often there are many pits which are econom... The ultimate pit may affect other aspects in the life of a mine such as economical, technical, environmental, and social aspects. What makes it even more complex is that most often there are many pits which are economically minable. This calls for a heuristic approach to determine which of these pits is the ultimate pit. This study presents a means of selecting an ultimate pit during design operations of the Hebei Limestone mine. During optimization processes of the mine, many pit shells were created using Whittle Software. Normally, Whittle Software optimizes these processes and assigns a revenue factor of 1 for the ultimate pit. Unfortunately, the pit shells created did not satisfy the criteria with a revenue factor of 1 based on the parameters. As a result of this, statistical analysis was implemented to further understand the relationship, variability, and correlation of the pit shells created (data). Correlation Analysis, K-means++ Analysis, Principal Component Analysis, and Generalized Linear models were used in the analysis of the pit shells created. The results portray a salient relationship of the optimization variables. In addition, the proposed method was tested on Whittle Sample projects which satisfy the selection of ultimate pit selection with a revenue factor of 1. The results show that the proposed model produced almost the same results as the Whittle model with a revenue factor of 1 and was also able to determine the ultimate pit in cases which did not satisfy the Whittle selection criteria. 展开更多
关键词 Ultimate Pit Statistical Analysis Pit Shells VARIABLES Mine Planning CLUSTERS
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Design and Research of Active Gravity Unloading Device for Large Aperture Optical Mirror
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作者 Qiuyue Yu Zhaoming Wang +6 位作者 Qiushi Yang Wen Guo Chunlin Li Yonggang Wang Mengjuan Li jianhua zhang Chao Wang 《Optics and Photonics Journal》 2023年第7期167-177,共11页
The large aperture optical mirror for space is processed and tested in the gravity environment on the ground. After entering space, gravity disappears due to the change of environment, and the mirror surface that has ... The large aperture optical mirror for space is processed and tested in the gravity environment on the ground. After entering space, gravity disappears due to the change of environment, and the mirror surface that has met the engineering requirements on the ground will change, seriously affecting the imaging quality. In order to eliminate the influence of gravity and to ensure the consistency of space and ground, gravity unloading must be performed. In order to meet the requirements of processing and testing for the large aperture space mirror in the state of vertical optical axis, a universal gravity unloading device was proposed. It was an active support and used air cylinders to provide accurate unloading force. First, the design flow of gravity unloading was introduced;then the detailed design of the mechanical structure and control system was given;then the performance parameters of the two types of cylinders were tested and compared, including the force-pressure relationship curve and the force-position relationship curve;finally, the experimental verification of the gravity unloading device was carried out;for a mirror with an aperture of ?2100 mm, the gravity unloading device was designed and a vertical detection optical path was built. The test results showed that by using this gravity unloading device, the actual processing surface accuracy of the mirror was better than 1/50λ-RMS, which met the application requirement of the optical system. Thus, it can be seen that using this gravity unloading device can effectively unload the gravity of the mirror and realize the accurate processing and measurement of the mirror surface. . 展开更多
关键词 Optical Mirror Large Aperture Active Support Gravity Unloading
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具有交联结构的热重排聚合物膜的制备及气体分离性能 被引量:2
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作者 贺磊 鲁云华 +4 位作者 张兼华 侯蒙杰 肖国勇 胡知之 王同华 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第5期1-8,共8页
采用不同摩尔比的9,9’-双[4-(4-硝基-3-羟基苯氧基)苯基]芴(BAHPPF)、3,5-二氨基苯甲酸(DABA)与六氟二酐(6FDA)进行共聚,再经热处理后得到一系列聚酰亚胺(PI)膜和具有交联结构的热重排(TR)聚合物膜。结果表明,随着热处理温度升高,热重... 采用不同摩尔比的9,9’-双[4-(4-硝基-3-羟基苯氧基)苯基]芴(BAHPPF)、3,5-二氨基苯甲酸(DABA)与六氟二酐(6FDA)进行共聚,再经热处理后得到一系列聚酰亚胺(PI)膜和具有交联结构的热重排(TR)聚合物膜。结果表明,随着热处理温度升高,热重排和交联反应同时发生,显著提高了层间距和膜材料对5种气体的渗透性。此外,随着DABA摩尔比增加,PI膜的玻璃化转变温度(T_(g))和热分解温度稍有提升;同时,TR膜材料对H_(2),CO_(2),N_(2),O_(2)和CH_(4)的渗透性和理想选择性也获得了提高。其中,TR-7:3膜表现出了最高的气体渗透性,对H_(2),CO_(2),O_(2),N_(2)和CH_(4)的渗透性分别达到了320.9 Barrers,369.7 Barrers,54.3 Barrers,15.0 Barrers和11 Barrers;同时,TR-7:3和TR-6:4膜对CO_(2)/CH_(4)的理想选择性为33.6和40.6,接近2008年的Robeson上限;而TR-9:1和TR-8:2膜对O_(2)/N_(2)的分离性能则超过了2008年的上限。 展开更多
关键词 热重排聚合物 气体分离 交联 渗透性 选择性
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碳在锂离子电池硅碳复合材料中的作用 被引量:5
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作者 张伟 齐小鹏 +3 位作者 方升 张健华 史碧梦 杨娟玉 《化学进展》 SCIE CAS CSCD 北大核心 2020年第4期454-466,共13页
随着低比容量硅碳复合材料(<500 mAh/g)在锂离子电池中的商业化应用,硅基负极材料也从实验室研究走向了产业化发展。近年来的研究工作中,许多方法被用来解决硅在循环过程中体积变化(>300%)所带来的一系列问题。在材料结构方面,从... 随着低比容量硅碳复合材料(<500 mAh/g)在锂离子电池中的商业化应用,硅基负极材料也从实验室研究走向了产业化发展。近年来的研究工作中,许多方法被用来解决硅在循环过程中体积变化(>300%)所带来的一系列问题。在材料结构方面,从最初的硅材料纳米化、硅与其他材料复合等技术手段转变到了硅碳复合材料二次颗粒的结构设计、表面包覆层设计等方法;在应用性能方面,除了早期文献报道的材料比容量、循环性能等参数外,还增加了材料比表面积、振实密度、首次及循环库仑效率等更符合电池实际应用要求的性能参数研究,从而极大地推动了硅基负极材料的商业化应用进程。本文首先综述了近年来硅碳复合材料组成、结构设计的发展脉络,进一步分析了由石墨、软碳、硬碳、碳纤维和石墨烯等碳源合成的硅碳复合材料的结构特点,并对其电化学性能进行分析对比,总结了碳在硅碳复合材料结构及其性能上发挥的作用。最后,对硅碳复合材料制备过程中的结构设计要求和碳材料的选择进行了分析和展望。 展开更多
关键词 锂离子电池 硅碳复合材料 镶嵌结构 硬碳 软碳
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The Interdisciplinary Research of Big Data and Wireless Channel: A Cluster-Nuclei Based Channel Model 被引量:24
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作者 jianhua zhang 《China Communications》 SCIE CSCD 2016年第S2期14-26,共13页
Recently,internet stimulates the explosive progress of knowledge discovery in big volume data resource,to dig the valuable and hidden rules by computing.Simultaneously,the wireless channel measurement data reveals big... Recently,internet stimulates the explosive progress of knowledge discovery in big volume data resource,to dig the valuable and hidden rules by computing.Simultaneously,the wireless channel measurement data reveals big volume feature,considering the massive antennas,huge bandwidth and versatile application scenarios.This article firstly presents a comprehensive survey of channel measurement and modeling research for mobile communication,especially for 5th Generation(5G) and beyond.Considering the big data research progress,then a cluster-nuclei based model is proposed,which takes advantages of both the stochastical model and deterministic model.The novel model has low complexity with the limited number of cluster-nuclei while the cluster-nuclei has the physical mapping to real propagation objects.Combining the channel properties variation principles with antenna size,frequency,mobility and scenario dug from the channel data,the proposed model can be expanded in versatile application to support future mobile research. 展开更多
关键词 channel model big data 5G massive MIMO machine learning CLUSTER
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