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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 840-851页

作者： Wei Xu yufeng Guo Tianhui Meng Yingwei wang Jilai yu the School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China

To improve the economic efficiency of urban integrated energy systems(UIESs)and mitigate day-ahead dispatch uncertainty,this paper presents an interconnected UIES and transmission system(TS)model based on distributed robust ***,interconnections are established between a TS and multiple UIESs,as well as among different UIESs,each incorporating multiple energy *** Bregman alternating direction method with multipliers(BADMM)is then applied to multi-block problems,ensuring the privacy of each energy system operator(ESO).Second,robust optimization based on wind probability distribution information is implemented for each ESO to address dispatch *** column and constraint generation(C&CG)algorithm is then employed to solve the robust ***,to tackle the convergence and practicability issues overlooked in the existing studies,an external C&CG with an internal BADMM and corresponding acceleration strategy is ***,numerical results demonstrate that the adoption of the proposed model and method for absorbing wind power and managing its uncertainty results in economic benefits.

关键词： Distributed robust optimization distributionally robust dispatch urban integrated energy system transmission system external column and constraint generation(C&CG) internal Bregman alternating direction method with multipliers(BADMM)

Kinematic calibration method with high measurement efficiency and robust identification for hybrid machine tools

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Chinese Journal of Aeronautics 2024年第3期37卷 468-482页

作者： Liping wang Mengyu LI Guang yu Weitao LI Xiangyu KONG State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipment and Control Beijing 100084China

Geometric error is the main factor affecting the machining accuracy of hybrid machine *** calibration is an effective way to improve the geometric accuracy of hybrid machine *** necessity to measure both position and orientation at each pose,as well as the instability of identification in case of incomplete measurements,severely affects the application of traditional calibration *** this study,a kinematic calibration method with high measurement efficiency and robust identification is proposed to improve the kinematic accuracy of a five-axis hybrid machine ***,the configuration is introduced,and an error model is ***,by investigating the mechanism error characteristics,a measurement scheme that only requires tool centre point position error measurement and one alignment operation is ***,by analysing the effects of unmeasured degrees of freedom(DOFs)on other DOFs,an improved nonlinear least squares method based on virtual measurement values is proposed to achieve stable parameter identification in case of incomplete measurement,without introducing additional ***,the proposed calibration method is verified through simulations and *** proposed method can efficiently accomplish the kinematic calibration of the hybrid machine *** accuracy of the hybrid machine tool is significantly improved after calibration,satisfying actual aerospace machining requirements.

关键词： Hybrid machine tool Calibration Measurement scheme Improved nonlinear least squares method Virtual measurement values

Online estimation and characteristic analysis of double nugget diameters during aluminum/steel resistance spot welding process

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Journal of Iron and Steel Research International 2024年第8期31卷 2053-2067页

作者： Kang Zhou Wen-xiao yu Bao-kai Ren Gang wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Online estimation of the double nugget diameters was performed by means of a back propagation neural *** double nugget diameters were obtained using actual welding experiment and numerical simulation,according to different characteristics of aluminum nugget and steel *** input of the neural network was some key characteristic parameters extracted from dynamic power signal,which were peak point,knee point and their variation rate over time,as well as heat energy delivered into the welding *** architecture of the neural network was confirmed by confirming the number of neurons in hidden layer through a series of *** key parameters of the neural network were obtained by means of training 81 arrays of data ***,the neural network was used to test the remaining 20 arrays of verifying data set,and the results showed that both of the mean errors for the two nugget diameters were below 3%.In addition,corresponding analyses showed that the accuracy of two nugget diameters was higher than that of tensile-shear strength.

关键词： Resistance spot welding Aluminum Steel Double nugget Dynamic power signal.Neural network

Investigation of electrostatically tunable adhesion and instability of flying head slider

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Friction 2024年第3期12卷 462-473页

作者： Fan ZHANG yu wang yueqiang HU Mingquan ZHANG Baotong LI School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China National Engineering Research Center for High Efficiency Grinding College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

The interfacial adhesion between microstructures is inevitable in a micro-electro-mechanical system(e.g.,hard disk drive(HDD)),which may lead to complicated microtribodynamics *** research has investigated the effect of surface potential on the interfacial adhesion and microtribodynamics of the head–disk interface(HDI)in an HDD.A dynamic continuum surface force model,where the electrowetting is considered,is proposed to evaluate the interfacial interaction,and then employed into a two-degree-of-freedom(2DOF)model to theoretically analyze the potential influence mechanism on the *** results confirm that the elimination of potential can effectively repress the adhesion retention,which is further proved by the measured slider response with a laser Doppler vibrometer(LDV).Moreover,the effect of the potential on the adhesion-induced instability is also analyzed through the phase *** tells that the critical stable flying height can be lowered with the elimination of potential.

关键词： electric field(EF) retention instability adhesion

Modification of Melting Combustion Kinetic Model of Fine Ash from Entrained-Flow Gasifier

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Journal of Thermal Science 2024年第1期33卷 300-310页

作者： wang Wenyu LI Wei LU yu REN Qiangqiang Lyu Qinggang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China

Coal gasification technology is a prominent technology in the coal chemical industry and serves as the fundamental basis for various process industries,including coal-based chemicals,coal-based liquid fuels,Integrated Gasification Combined Cycle(IGCC) power generation,multi-generation systems,hydrogen production,and fuel *** gasification process generates significant quantities of ash residue,with annual emissions exceeding tens of millions of tons and accumulation reaching hundreds of millions of ***,there is an urgent need to investigate methods for its *** combustion of gasified fine ash(GFA) was conducted in a tube furnace,and the conventional shrinking core model was modified to accurately predict the combustion behaviors at different temperatures(900℃-1500℃).We divided the reaction temperatures into three ranges,which is defined as unmelted combustion(TFT) and mixed combustion(DTFT),the surface ash of GFA grains fell off,and the residual carbon and gas-phase reactants were nearly no longer affected by the diffusion resistance,thus significantly accelerated the reaction of internal residual *** order to predict the melt combustion process more accurately,the time term of the shrinkage core model(SCM) is modified,and the effective diffusion coefficient of T>FT is defined.

关键词： fine ash melting combustion kinetic model combustion characteristics

Prenatal amoxicillin exposure induces developmental toxicity in fetal mice and its characteristics

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Journal of Environmental Sciences 2024年第3期137卷 287-301页

作者： Yongguo Dai yu Peng Wen Hu Yi Liu Hui wang Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Department of Pharmacy Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Amoxicillin,a widely used antibiotic in human and veterinary pharmaceuticals,is now considered as an“emerging contaminant”because it exists widespreadly in the environment and brings a series of adverse ***,systematic studies about the developmental toxicity of amoxicillin are still *** explored the potential effects of amoxicillin exposure on pregnancy outcomes,maternal/fetal serum phenotypes,and fetal multiple organ development in mice,at different doses(75,150,300 mg/(kg·day))during late-pregnancy,or at a dose of 300 mg/(kg·day)during different stages(mid-/latepregnancy)and courses(single-/multi-course).Results showed that prenatal amoxicillin exposure(PAmE)had no significant infuence on the body weights of dams,but it could inhibit the physical development and reduce the survival rate of fetuses,especially during the ***,PAmE altered multiple maternal/fetal serum phenotypes,especially in *** multi-organ function results showed that PAmE inhibited testicular/adrenal steroid synthesis,long bone/cartilage and hippocampal development,and enhanced ovarian steroid synthesis and hepatic glycogenesis/lipogenesis,and the order of severity might be gonad(testis,ovary)>liver>*** analysis found that PAmE-induced multiorgan developmental and functional alterations had differences in stages,courses and fetal gender,and the most obvious changes might be in high-dose,late-pregnancy and multicourse,but there was no typical rule of a dose-response *** conclusion,this study confirmed that PAmE could cause abnormal development and multi-organ function alterations,which deepens our understanding of the risk of PAmE and provides an experimental basis for further exploration of the long-term harm.

关键词： Amoxicillin Prenatal exposure Fetal development Organ function Developmental toxicity

Soil and microbial C:N:P stoichiometries play vital roles in regulating P transformation in agricultural ecosystems:A review

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Pedosphere 2024年第1期34卷 44-51页

作者： Guanglei CHEN Jiahui yuAN Shenqiang wang yuting LIANG Dengjun wang Yiyong ZHU yu wang State Key Laboratory of Soil and Sustainable Agriculture Changshu National Agro-Ecosystem Observation and Research StationInstitute of Soil ScienceChinese Academy of SciencesNanjing 210008China School of Life Sciences Jiangsu Normal UniversityXuzhou 221000China School of Fisheries Aquacultureand Aquatic SciencesAuburn UniversityAuburn AL 36849USA Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization College of Resources and Environmental ScienceNanjing Agricultural UniversityNanjing 210095China

Stoichiometry plays a crucial role in biogeochemical cycles and can modulate soil nutrient availability and functions. In agricultural ecosystems,phosphorus(P) fertilizers(organic or chemical) are often applied to achieve high crop yields. However, P is readily fixed by soil particles, leading to low P use efficiency. Therefore, understanding the role of carbon:nitrogen:P stoichiometries of soil and microorganisms in soil P transformation is of great significance for P management in agriculture. This paper provides a comprehensive review of the recent research on stoichiometry effect on soil P transformation in agricultural ecosystems. Soil microorganisms play an important role in the transformation of soil non-labile inorganic P to microbial biomass P by regulating microbial biomass stoichiometry. They also mobilize soil unavailable organic P into available P by changing ecoenzyme stoichiometry. Organic materials, such as manure and straw, play an important role in promoting the transformation of insoluble P into available P as well. Additionally, periphytic biofilms can reduce P loss from rice field ecosystems. Agricultural stoichiometries are different from those of natural ecosystems and thereby should receive more attention due to the influences of anthropogenic factors. Therefore, it is necessary to conduct further stoichiometry research on the soil biochemical mechanisms underlying P transformation in agricultural ecosystems. In conclusion, understanding stoichiometry impact on soil P transformation is crucial for P management in agricultural ecosystems.

关键词： ecoenzyme microbial biomass microbial community microorganism P availability periphytic biofilm soil P transformation

Gastric cancer immunotherapy:A scientometric and clinical trial review

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World Journal of Gastroenterology 2024年第2期30卷 196-198页

作者： Qian-Cheng Du Xin-yu wang Hua yu Thoracic Surgery Shanghai Xuhui Central HospitalShanghai 200031China Thyroid Breast and Vascular SurgeryShanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China Department of General Surgery Shanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China

This letter is intended to arouse your interest in a recent review of comprehensive scientometrics and clinical trials on immunotherapy for gastric cancer(GC).Our study reviews recent advances in immunotherapy in the field of GC and highlights its new prospects as a treatment for *** research reveals China’s leadership in this field,as well as new therapeutic strategies such as immune checkpoint inhibitors,cellular immunotherapy,and *** combined findings highlight the potential of immunotherapy to improve survival and quality of life in patients with stomach *** believe that this study will provide important guidance for the future direction of the GC treatment field.

关键词： Gastric cancer Immunotherapy Bibliometrics Comment Therapeutic strategies

More tree growth reduction due to consecutive drought and its legacy effect for a semiarid larch plantation in Northwest China

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Journal of Forestry Research 2024年第2期35卷 188-196页

作者： Yanfang Wan Pengtao yu Yanhui wang Jiamei Li yushi Bai Yipeng yu Bingbing Liu Xiaocha Wei Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China

Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more ***,it is poorly understood how tree growth is affected by different drought *** 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate *** this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch *** found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry *** induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy *** reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry *** results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry *** results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas.

关键词： Tree rings Drought effects Legacy effects Growth-climate relationships Larix principis-rupprechtii

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

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Petroleum Science 2024年第3期21卷 1865-1874页

作者： Ji wang Ning Qi Hong-Yao Yin yu-Jun Feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu Yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation