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Temperature-Dependent Thermal Conductivity and Absorption Coefficient Identification of Quartz Window up to 1100 K

Journal of Thermal Science 2023年第1期32卷 44-58页

作者： SHI Yu CHEN Xue SUN Chuang xia xin-lin School of Energy Science and Engineering Harbin Institute of Technology(HIT)Harbin 150001China

The temperature-dependent absorption coefficient and thermal conductivity of a quartz window are obtained through experimental tests at a wide range of temperatures.A Fourier transform infrared spectrometer with a heated cavity is used for performing the transmittance measurements.The spectral absorption coefficient of the quartz window is inverted by the transmittance information at different temperatures using a genetic algorithm.Then,a quartz window-graphite plate-quartz window multilayer structure is designed,and the transient response of the structure subjected to high-temperature heating is recorded by a self-designed setup.Cooperating with the above absorption coefficient,a non-gray radiative-conductive heat transfer model is built for the multilayer structure,and the intrinsic thermal conductivity of the quartz window is identified.Finally,the effects of the temperature-dependent absorption coefficient and spectral selective features of the medium on the heat transfer characteristics are discussed.The results show that the absorption coefficient gradually increases with temperature.The intrinsic thermal conductivity of the quartz window varies from 1.35 to 2.52 W/(m·K)as the temperature rises,while the effective thermal conductivity is higher than the intrinsic thermal conductivity due to thermal radiation,specifically 26.4%higher at 1100 K.In addition,it is found that the influence of the temperature-dependent absorption coefficient on temperature of unheated side shows a trend of first increasing and then decreasing.When the absorption coefficient varies greatly with wavelength,a non-gray radiative-conductive heat transfer model should be built for the semitransparent materials.

关键词： semitransparent material quartz window non-gray body absorption coefficient thermal conductivity

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Enhanced photocatalytic N_(2) fixation using KNbO3/Bi_(4)O_(5)Br_(2) type II heterojunction

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 85-97页

作者： lin Yue Zhihao Zeng Xujie Ren Shude Yuan Chuanqi xia xin Hu Leihong Zhao Lvchao Zhuang Yiming He Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China Department of Materials Science and Engineering Zhejiang Normal UniversityJinhua 321004China

The fabrication of heterojunction catalysts is an effective strategy to enhance charge separation efficiency,thus boosting the performance of photocatalysts.This work presents the synthesis and investigation of a novel KNbO_(3)/Bi_(4)O_(5)Br_(2) heterostructure catalyst for photocatalytic N_(2)-to-NH_(3) conversion under light illumination.While morphology analysis revealed KNbO_(3) microcubes embedded within Bi_(4)O_(5)Br_(2) nanosheets,the composite exhibited no significant improvement in specific surface area or optical property compared to Bi_(4)O_(5)Br_(2) due to the relatively wide band gap and low surface area of KNbO_(3).The main contribution lies in the enhanced separation efficiency of photogenerated electrons and holes.Besides,the band structure analysis suggests that KNbO_(3) and Bi_(4)O_(5)Br_(2) exhibit suitable band potentials to form a type II heterojunction.Benefiting from the higher Fermi level of KNbO_(3) than Bi_(4)O_(5)Br_(2),the electron drift at the contact region thus occurs and leads to the formation of a built-in electric field with the direction from KNbO_(3) to Bi_(4)O_(5)Br_(2),accelerating electron migration and improving the operational efficiency of the photocatalysts.Consequently,the KNbO_(3)/Bi_(4)O_(5)Br_(2) catalyst shows an increased photoactivity,achieving an NH_(3) generation rate 1.78 and 1.58 times those of KNbO_(3) and Bi_(4)O_(5)Br_(2),respectively.This work may offer valuable insights for the design and synthesis of heterojunction composite photocatalysts.

关键词： KNbO_(3)/Bi_(4)O_(5)Br_(2) heterojunction photocatalytic N_(2)fixation charge separation

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Analysis on characteristics of extreme precipitation indices and atmospheric circulation in Northern Shanxi

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Research in Cold and Arid Regions 2024年第2期16卷 84-97页

作者： xia Cai Yan Song lin Cai xin Su GuiHua Liang YanMing Xu Shuozhou Meteorological Bureau of Shanxi Province China Meteorological Administration Training Center Heze University of Shandong Province Huafeng Meteorological Media Group Shuocheng Meteorological Bureau

This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020, and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average reanalysis data. The study employs techniques such as empirical orthogonal function(EOF) decomposition, MannKendall mutation and other methods to investigate the spatiotemporal distribution of extreme precipitation index in northern Shanxi and their correlation with atmospheric circulation. The research results show that: the absolute index, relative index, intensity index and sustained dry period index(CDD) in the continuous index appear from southwest to northeast. The spatial distribution characteristics of the central region decrease, while the continuous wet period(CWD) decreases from the central to the east and west. The three indices Rx1day, Rx5day, and CWD mutated in 1978, 1975, and 1983 respectively, and other extreme precipitation indices all appeared in a sudden change from a low-value period to a high-value period occurred around 2010. In the high-value years of the summer extreme precipitation index, there is a significant negative anomaly in the height field in the mid-high latitude regions of Eurasia. Northern Shanxi is controlled by a broad low-pressure trough in the Lake Baikal area.Water vapor transported via the east, west, and south routes converges in the northern Shanxi region and encounters cold air from the north. There is a strong upward motion anomaly at 500 hPa in the troposphere, and the dynamic conditions of upper-level divergence and lower-level convergence lead to more summer extreme precipitation in the northern Shanxi region. Conversely, in the low-value years of the summer extreme precipitation index, northern Shanxi is affected by a strong high-pressure ridge north of Lake Baikal. There is a downward motion anomaly at 500 hPa, and the northern Shanxi region lacks water vapor. The cold and warm air cannot converge, and both the water vapor conditions and dynamic cond

关键词： Northern Shanxi Extreme precipitation indices Spatio-temporal distribution and evolution Mutations Atmospheric circulation anomaly

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Classification and spectrum optimization method of grease based on infrared spectrum

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Friction 2024年第6期12卷 1154-1164页

作者： xin FENG Yanqiu xia Peiyuan XIE xiaohe LI School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The infrared(IR)absorption spectral data of 63 kinds of lubricating greases containing six different types of thickeners were obtained using the IR spectroscopy.The Kohonen neural network algorithm was used to identify the type of the lubricating grease.The results show that this machine learning method can effectively eliminate the interference fringes in the IR spectrum,and complete the feature selection and dimensionality reduction of the high-dimensional spectral data.The 63 kinds of greases exhibit spatial clustering under certain IR spectrum recognition spectral bands,which are linked to characteristic peaks of lubricating greases and improve the recognition accuracy of these greases.The model achieved recognition accuracy of 100.00%,96.08%,94.87%,100.00%,and 87.50%for polyurea grease,calcium sulfonate composite grease,aluminum(Al)-based grease,bentonite grease,and lithium-based grease,respectively.Based on the different IR absorption spectrum bands produced by each kind of lubricating grease,the three-dimensional spatial distribution map of the lubricating grease drawn also verifies the accuracy of classification while recognizing the accuracy.This paper demonstrates fast recognition speed and high accuracy,proving that the Kohonen neural network algorithm has an efficient recognition ability for identifying the types of the lubricating grease.

关键词： grease infrared(IR)spectroscopy layered Kohonen network species recognition spectrum band optimization

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Drug repurposing for cancer therapy

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1981-2013页

作者： Ying xia Ming Sun Hai Huang Wei-lin Jin Center for Clinical Laboratories The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004PR China The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine Guiyang 550001PR China School of Clinical Laboratory Science Guizhou Medical UniversityGuiyang 550004PR China Division of Gastroenterology and Hepatology Department of Medicine andDepartment of OncologySidney Kimmel Comprehensive Cancer CenterJohns Hopkins University School of MedicineBaltimoreMD 21287USA Institute of Cancer Neuroscience Medical Frontier Innovation Research CenterThe First Hospital of Lanzhou UniversityThe First Clinical Medical College of Lanzhou UniversityLanzhou 730000PR China

Cancer,a complex and multifactorial disease,presents a significant challenge to global health.Despite significant advances in surgical,radiotherapeutic and immunological approaches,which have improved cancer treatment outcomes,drug therapy continues to serve as a key therapeutic strategy.However,the clinical efficacy of drug therapy is often constrained by drug resistance and severe toxic side effects,and thus there remains a critical need to develop novel cancer therapeutics.One promising strategy that has received widespread attention in recent years is drug repurposing:the identification of new applications for existing,clinically approved drugs.Drug repurposing possesses several inherent advantages in the context of cancer treatment since repurposed drugs are typically cost-effective,proven to be safe,and can significantly expedite the drug development process due to their already established safety profiles.In light of this,the present review offers a comprehensive overview of the various methods employed in drug repurposing,specifically focusing on the repurposing of drugs to treat cancer.We describe the antitumor properties of candidate drugs,and discuss in detail how they target both the hallmarks of cancer in tumor cells and the surrounding tumor microenvironment.In addition,we examine the innovative strategy of integrating drug repurposing with nanotechnology to enhance topical drug delivery.We also emphasize the critical role that repurposed drugs can play when used as part of a combination therapy regimen.To conclude,we outline the challenges associated with repurposing drugs and consider the future prospects of these repurposed drugs transitioning into clinical application.

关键词： drugs integrating spite

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Unified method for typical gear failure modeling and stiffness calculation based on the matrix equation

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Frontiers of Mechanical Engineering 2024年第3期19卷 93-114页

作者： Fanshan MENG xin ZHANG Heng xia Jiaxu WANG School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing UniversityChongqing 400044China

The failure types in gear systems vary,with typical ones mainly including pitting,cracking,wear,and broken teeth.Different modeling and stiffness calculation methods have been developed for various gear failure types.A unified method for typical gear failure modeling and stiffness calculation is introduced in this study by considering the deviations in the time-varying meshing stiffness(TVMS)of faulty gears resulting from the use of different methods.Specifically,a gear tooth is discretized into a large number of microelements expressed with a matrix,and unified models of typical gear failures are built by adjusting the values of the matrix microelements.The values and positions of the microelements in the tooth failure model matrix have the same physical meaning as the parameter variables in the potential energy method(PEM),so the matrix-based failure model can be perfectly matched with PEM.Afterward,a unified method for TVMS is established.Modeling of healthy and faulty gears with pitting,wear,crack,and broken tooth is performed with the matrix equation,and the corresponding TVMS values are calculated by incorporating the matrix models with PEM.On the basis of the results,the mechanism of typical fault types that affect TVMS is analyzed,and the conclusions are verified through the finite element method.The developed unified method is a promising technique for studying the dynamic response characteristics of gear systems with different failure types because of its superiority in eliminating stiffness deviations.

关键词： gears matrix equation failure modeling TVMS calculation unified method

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Association of complement components with risk of colorectal cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2168-2180页

作者： xiao-lin Zhu Lu Zhang Su-xia Qi Department of Gastroenterology Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina Department of Medical Administration Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina

BACKGROUND Complement components could contribute to the tumor microenvironment and the systemic immune response.Nevertheless,their role in colorectal cancer(CRC)remains a contentious subject.AIM To elucidate the relationship between complement components and CRC risk and clinical characteristics.METHODS Searches were conducted in PubMed,the Cochrane Library,and the China National Knowledge Infrastructure database until June 1,2023.We included cohort studies encompassing participants aged≥18 years,investigating the association between complement components and CRC.The studies were of moderate quality or above,as determined by the Agency for Healthcare Research and Quality.The meta-analysis employed fixed-effects or random-effects models based on the I^(2)test,utilizing risk ratio(RR)and their corresponding 95%confidence interval(CI)for outcomes.Sensitivity and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of heterogeneity.RESULTS Data from 15 studies,comprising 1631 participants that met the inclusion criteria,were included in the meta-analysis.Our findings indicated that protein levels of cluster of differentiation 46(CD46)(RR=3.66,95%CI:1.75-7.64,P<0.001),CD59(RR=2.86,95%CI:1.36-6.01,P=0.005),and component 1(C1)(RR=5.88,95%CI:1.75-19.73,P=0.004)and serum levels of C3(standardized mean difference=1.82,95%CI:0.06-3.58,P=0.040)were significantly elevated in patients with CRC compared to healthy controls.Strong expression of CD55 or CD59 was associated with a higher incidence of lymph node metastasis,whereas strong CD46 expression correlated with a higher incidence of tumor differentiation compared to low CD46 expression(P<0.05 for all).Although specific pooled results demonstrated notable heterogeneity,subgroup analyses pointed to regional differences as the primary source of inconsistency among the studies.CONCLUSION Our analysis underscores that increased levels of specific complement components are associated with a heightened risk of CRC,emphasi

关键词： Complement components Colorectal cancer Lymph node metastasis Systematic review Meta-analysis

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Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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China Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG Guo-xing xia xin-lu GUO Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological features.Firstly,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain synthesis.Secondly,the screw theory is employed to analyze the degree of freedom(DoF)of the capture mechanism.Then,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried out.Combined with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried out.Furthermore,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are analyzed.Finally,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is completed.The work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

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Prediction of Lubricant Physicochemical Properties Based on Gaussian Copula Data Expansion

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 161-174页

作者： Feng xin Yang Rui Xie Peiyuan xia Yanqiu School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO40,and PriEco3000 component in a composite base oil system on the performance of lubricants.The study was conducted under small laboratory sample conditions,and a data expansion method using the Gaussian Copula function was proposed to improve the prediction ability of the hybrid model.The study also compared four optimization algorithms,sticky mushroom algorithm(SMA),genetic algorithm(GA),whale optimization algorithm(WOA),and seagull optimization algorithm(SOA),to predict the kinematic viscosity at 40℃,kinematic viscosity at 100℃,viscosity index,and oxidation induction time performance of the lubricant.The results showed that the Gaussian Copula function data expansion method improved the prediction ability of the hybrid model in the case of small samples.The SOA-GBDT hybrid model had the fastest convergence speed for the samples and the best prediction effect,with determination coefficients(R^(2))for the four indicators of lubricants reaching 0.98,0.99,0.96 and 0.96,respectively.Thus,this model can significantly reduce the model’s prediction error and has good prediction ability.

关键词： base oil data augmentation machine learning performance prediction seagull algorithm

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Copper Metabolism and Cuproptosis:Molecular Mechanisms and Therapeutic Perspectives in Neurodegenerative Diseases

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Current Medical Science 2024年第1期44卷 28-50页

作者： xiao-xia BAN Hao WAN xin-xing WAN Ya-ting TAN Xi-min HU Hong-xia BAN xin-yu CHEN Kun HUANG Qi ZHANG Kun XIONG Department of Human Anatomy and Neurobiology School of Basic Medical ScienceCentral South UniversityChangsha 430013China Department of Endocrinology Third Xiangya HospitalCentral South UniversityChangsha 430013China Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 430013China Affiliated Hospital Inner Mongolia Medical UniversityHohhot 010050China Key Laboratory of Emergency and Trauma of Ministry of Education Hainan Medical UniversityHaikou 571199China Hunan Key Laboratory of Ophthalmology Changsha 430013China

Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess can adversely affect cellular function.Therefore,copper homeostasis is stringently regulated.Recent studies suggest that copper can trigger a specific form of cell death,namely,cuproptosis,which is triggered by excessive levels of intracellular copper.Cuproptosis induces the aggregation of mitochondrial lipoylated proteins,and the loss of iron-sulfur cluster proteins.In neurodegenerative diseases,the pathogenesis and progression of neurological disorders are linked to copper homeostasis.This review summarizes the advances in copper homeostasis and cuproptosis in the nervous system and neurodegenerative diseases.This offers research perspectives that provide new insights into the targeted treatment of neurodegenerative diseases based on cuproptosis.

关键词： cuproptosis copper metabolism copper homeostasis neurodegeneration neurodegenerativedisease

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