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Journal of Environmental Sciences 2007年第11期19卷 1367-1372页

作者： wang da-yong YANG Peng Department of Genetics and Developmental Biology Southeast University Nanjing 210009 China Key Laboratory of Developmental Genes and Human Disease Ministry of Education of China Nanjing 210009 China

Whether the multi-biological toxicity from lead exposure could be transferred to progeny has not been clarified. In the present study, we explored the Caenorhabditis elegans to analyze the multiple toxicities from lead exposure and their possibly transferable properties. The lead exposure could cause series of severe multi-biological defects with a concentration-dependent manner by affecting the endpoints of life span, development, reproduction and locomotion behaviors in nematodes. Moreover, most of these toxicities could be transferred to progeny from lead exposed animals and some of the defects in progeny appeared even more severe than in their parents, such as the body sizes and mean life spans. We summarized the defects caused by lead exposure into three groups according to their transferable properties or rescue patterns. That is, the defects caused by lead exposure could be largely, or partially, or became even more severe in progeny animals. Therefore, our results suggest that lead exposure can cause severely multi-biological defects, and most of these multiple toxicities can be considered as transferable for exposed animals in C. elegans.

关键词： lead exposure toxicity transferable phenotype behavior Caenorhabditis elegans

Endovascular treatment of intracranial aneurysms using coil embolization plus an Enterprise stent

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Chinese Medical Journal 2011年第4期124卷 611-614页

作者： XU Xiang SHANG Xiao-ming CUI Jian-zhong wang da-yong Department of Neurosurgery Tangshan Gongren Hospital Tangshan Hebei 063000 China Department of Cardiology Tangshan Gongren Hospital Tangshan Hebei 063000 China Department of Neurosurgery Tangshan Gongren Hospital Tangshan Hebei 063000 China

Background Several difficulties can arise from wide-neck cerebral aneurysms when treated with endovascular embolization. We aimed to investigate the effect of endovascular treatment of intracranial aneurysms using coil embolization plus an Enterprise stent.Methods Forty patients were treated with coil embolization plus an Enterprise stent between December 2008 and June 2010.Results The mortality of patients was 0. All stents were successfully implanted without any surgery-related complication.Conclusion The Enterprise stent has some advantages to be selected.

关键词： endovascular procedures aneurysm coil stents

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新型二氧化碳化学吸收剂研究进展

现代化工 2024年第7期44卷 51-56页

作者：王大勇谷小虎刘欧阳林雄超方梦祥河南神马氢化学有限责任公司河南平顶山467000 炼焦煤资源绿色开发全国重点实验室中国平煤神马集团河南平顶山467000 中国矿业大学(北京)化学与环境工程学院北京100083 浙江大学能源清洁利用国家重点实验室浙江杭州310027

介绍了新型二氧化碳化学吸收剂的研究进展,主要包括相变吸收剂、离子液体吸收剂、低共熔溶剂、非水吸收剂和催化解析,指出相变吸收剂吸收能力强,但解析能耗高,并存在一定的腐蚀性;离子液体吸收剂具有低挥发性、高化学稳定性、可调控性... 详细信息

介绍了新型二氧化碳化学吸收剂的研究进展,主要包括相变吸收剂、离子液体吸收剂、低共熔溶剂、非水吸收剂和催化解析,指出相变吸收剂吸收能力强,但解析能耗高,并存在一定的腐蚀性;离子液体吸收剂具有低挥发性、高化学稳定性、可调控性等优点,但存在合成复杂、成本高、黏度大等缺点;低共熔溶剂蒸汽压极低、溶解性能好、结构和性质具有可调性,黏度低,但是吸收量低,不适应低浓度二氧化碳场景;非水吸收剂具有腐蚀性低、解析能耗低,但无法管道输送,成本高;还可以在吸收剂中调控催化体系,可快速诱导吸收溶剂再生,降低再生能耗,但催化剂稳定性有待进一步加强。最后提出未来二氧化碳化学吸收剂可通过精细地分子设计和合成、引入新的功能基团,制备出成本更低、环境影响更小、吸收性能更强和热稳定性佳、再生能耗低的产品。

关键词：二氧化碳化学吸收法相变吸收剂离子液体吸收剂低共熔溶剂非水吸收剂

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

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Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying wang Shengling Si Hongli Li david da yong Chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan Zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment steps.An effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of PFCs.Conditions affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were studied.The optimum conditions were found to be 120℃,10 min,and 3 cycles,respectively.LC-MS/MS method was developed to obtain the optimal sensitivity specific to PFCs.The method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/g.To ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent contamination.The optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target compounds.Finally,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to 2019.It is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

Micro-power negative pressure wound technique reduces risk of incision infection following loop ileostomy closure

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 186-195页

作者： Deng-yong Xu Bing-Jun Bai Lina Shan Hui-Yan Wei Deng-Feng Lin Ya wang da wang Department of Colorectal Surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016Zhejiang ProvinceChina Department of Wound&Ostomy Care Clinic Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016Zhejiang ProvinceChina Department of Hospital Infection Control Zhejiang Cancer HospitalHangzhou 310005Zhejiang ProvinceChina

BACKGROUND Prophylactic loop ileostomy is an effective way to reduce the clinical severity of anastomotic leakage following radical resection of rectal cancer.Incisional surgical site infection(SSI)is a common complication after ileostomy closure.AIM To evaluate the efficacy and safety of the micro-power negative pressure wound technique(MPNPWT)in preventing incisional SSI.METHODS This was a prospective,randomized controlled clinical trial conducted at a single center.A total of 101 consecutive patients who underwent ileostomy closure after rectal cancer surgery with a prophylactic ileostomy were enrolled from January 2019 to December 2021.Patients were randomly allocated into an MPNPWT group and a control group.The MPNPWT group underwent intermittent suturing of the surgical incision with 2-0 Prolene and was covered with a micro-power negative pressure dressing.The surgical outcomes were compared between the MPNPWT(n=50)and control(n=51)groups.Risk factors for incisional SSI were identified using logistic regression.RESULTS There were no differences in baseline characteristics between the MPNPWT(n=50)and control groups(n=51).The incisional SSI rate was significantly higher in the control group than in the MPNPWT group(15.7%vs 2.0%,P=0.031).However,MPNPWT did not affect other surgical outcomes,including intra-abdominal complications,operative time,and blood loss.Postoperative hospital stay length and hospitalization costs did not differ significantly between the two groups(P=0.069 and 0.843,respectively).None of the patients experienced adverse effects of MPNPWT,including skin allergy,dermatitis,and pain.MPNPWT also helped heal the infected incision.Our study indicated that MPNPWT was an independent protective factor[odds ratio(OR)=0.005,P=0.025)]and diabetes was a risk factor(OR=26.575,P=0.029)for incisional SSI.CONCLUSION MPNPWT is an effective and safe way to prevent incisional SSI after loop ileostomy closure.

关键词： Micro-power negative pressure technique Ileostomy closure Incisional surgical site infection Infection prevention Postoperative incision

Quantized bound states around a vortex in anisotropic superconductors

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 146-155页

作者： Ke Xiang da wang Qiang-Hua wang National Laboratory of Solid State Microstructures&School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

The bound states around a vortex in anisotropic superconductors is a longstanding yet important issue.In this work,we develop a variational theory on the basis of the Andreev approximation to obtain the energy levels and wave functions of the low-energy quantized bound states in superconductors with anisotropic pairing on arbitrary Fermi surface.In the case of circular Fermi surface,the effective Schr¨odinger equation yielding the bound state energies gets back to the theory proposed by Volovik and Kopnin many years ago.Our generalization here enables us to prove the equidistant energy spectrum inside a vortex in a broader class of superconductors.More importantly,we are now able to obtain the wave functions of these bound states by projecting the quasiclassical wave function on the eigenmodes of the effective Schr¨odinger equation,going beyond the quasiclassical Eilenberger results,which,as we find,are sensitive to the scattering rate.For the case of isotropic Fermi surface,the spatial profile of the low-energy local density of states is dominated near the vortex center and elongates along the gap antinode directions,in addition to the ubiquitous Friedel oscillation arising from the quantum inteference neglected in the Eilenberger theory.Moreover,as a consequence of the pairing anisotropy,the quantized wave functions develop a peculiar distribution of winding number,which reduces stepwise towards the vortex center.Our work provides a flexible way to study the vortex bound states in the future.

关键词： vortex bound state anisotropic superconductor Andreev approximation

Long-term operation optimization of circulating cooling water systems under fouling conditions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 255-267页

作者： Jiarui Liang yong Tian Shutong Yang yong wang Ruiqi Yin Yufei wang School of Chemical Engineering and Environment China University of PetroleumBeijing102249China CHN Energy Xinjiang Chemical Co. LTDUrumqi830092China College of Mechanical and Transportation Engineering China University of PetroleumBeijing 102249China

Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.

关键词： Computer simulation Circulating water system Fouling Concentration cycle Optimization Variable frequency drive

Dynamic performance and parameter optimization of a half-vehicle system coupled with an inerter-based X-structure nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 85-110页

作者： yong wang Peili wang Haodong MENG Liqun CHEN .Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina Guangxi Key Laboratory of Automobile Components and Vehicle Technology Guangxi University of Science and TechnologyLiuzhou 545006Guangxi Zhuang Autonomous RegionChina School of Automotive Engineering Changzhou Institute of TechnologyChangzhou 213032Jiangsu ProvinceChina Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China

Inspired by the demand of improving the riding comfort and meeting the lightweight design of the vehicle, an inerter-based X-structure nonlinear energy sink(IXNES) is proposed and applied in the half-vehicle system to enhance the dynamic performance. The X-structure is used as a mechanism to realize the nonlinear stiffness characteristic of the NES, which can realize the flexibility, adjustability, high efficiency, and easy operation of nonlinear stiffness, and is convenient to apply in the vehicle suspension, and the inerter is applied to replacing the mass of the NES based on the mass amplification characteristic. The dynamic model of the half-vehicle system coupled with the IX-NES is established with the Lagrange theory, and the harmonic balance method(HBM) and the pseudo-arc-length method(PALM) are used to obtain the dynamic response under road harmonic excitation. The corresponding dynamic performance under road harmonic and random excitation is evaluated by six performance indices, and compared with that of the original half-vehicle system to show the benefits of the IX-NES. Furthermore, the structural parameters of the IX-NES are optimized with the genetic algorithm. The results show that for road harmonic and random excitation, using the IX-NES can greatly reduce the resonance peaks and root mean square(RMS) values of the front and rear suspension deflections and the front and rear dynamic tire loads, while the resonance peaks and RMS values of the vehicle body vertical and pitching accelerations are slightly larger.When the structural parameters of the IX-NES are optimized, the vehicle body vertical and pitching accelerations of the half-vehicle system could reduce by 2.41% and 1.16%,respectively, and the other dynamic performance indices are within the reasonable ranges.Thus, the IX-NES combines the advantages of the inerter, X-structure, and NES, which improves the dynamic performance of the half-vehicle system and provides an effective option for vibration attenuation in the vehicle engineering.

关键词： inerter X-structure nonlinear energy sink(NES) half-vehicle system dynamic performance

Availability evaluation of controller area networks under the influence of intermittent connection faults

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 555-568页

作者： Longkai wang Leiming ZHANG yong LEI State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China The 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210039China

Controller area networks(CANs),as one of the widely used fieldbuses in the industry,have been extended to the automation field with strict standards for safety and reliability.In practice,factors such as fatigue and insulation wear of the cables can cause intermittent connection(IC)faults to occur frequently in the CAN,which will affect the dynamic behavior and the safety of the system.Hence,quantitatively evaluating the performance of the CAN under the influence of IC faults is crucial to real-time health monitoring of the system.In this paper,a novel methodology is proposed for real-time quantitative evaluation of CAN availability when considering IC faults,with the system availability parameter being calculated based on the network state transition model.First,the causal relationship between IC fault and network error response is constructed,based on which the IC fault arrival rate is estimated.Second,the states of the network considering IC faults are analyzed,and the deterministic and stochastic Petri net(DSPN)model is applied to describe the transition relationship of the states.Then,the parameters of the DSPN model are determined and the availability of the system is calculated based on the probability distribution and physical meaning of markings in the DSPN model.A testbed is constructed and case studies are conducted to verify the proposed methodology under various experimental setups.Experimental results show that the estimation results obtained using the proposed method agree well with the actual values.

关键词： Controller area network Intermittent connection fault Arrival rate Deterministic and stochastic Petri net Availability evaluation

Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo wang Zhong Jiang Pei-da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining equipment.Most active vibration-isolation systems(AVIS)have been developed based on static loads.When a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy deteriorates.To solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining conditions.Vibration-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were conducted.The experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load conditions.This design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control