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Effect of electrochemical etching current on prepared perforated silicon structures for neutron detectors

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Frontiers of Materials Science 2013年第1期7卷 96-101页

作者： Xiao-Qiang FAN yong JIANG Chang-yong zhan Yu zou Jian-Chun WU Ning-Kang HUANG Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China Key Laboratory of Radiation Physics and Technology (Ministry of Education) Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China

Neutron detector based on perforated silicon structures backfilled with neutron converting materials could be operated at a low voltage and improves the detection efficiency of thermal neutron. It is found that the intrinsic detection efficiency of thermal neutron is affected by a lot of factors such as the geometry, size, and depth of the perforation and so on. In this study, the perforated silicon was prepared by electrochemical etching. Effect of etching current on geometry, size, and depth of the perforated silicon structures for neutron detectors was also reported.

关键词： neutron detector silicon electrochemical etching current

Image Fusion Based on Bioinspired Rattlesnake Visual Mechanism Under Lighting Environments of Day and Night Two Levels

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Journal of Bionic Engineering 2024年第3期21卷 1496-1510页

作者： yong Wang Hongmin zou College of Communication Engineering Jilin UniversityChangchun130012China

This study,grounded in Waxman fusion method,introduces an algorithm for the fusion of visible and infrared images,tailored to a two-level lighting environment,inspired by the mathematical model of the visual receptive field of rattlesnakes and the two-mode cells'*** research presented here is segmented into three *** the first segment,we design a preprocessing module to judge the ambient light intensity and divide the lighting environment into two levels:day and *** second segment proposes two distinct network structures designed specifically for these daytime and nighttime *** the daytime images,where visible light information is predominant,we feed the ON-VIS signal and the IR-enhanced visual signal into the central excitation and surrounding suppression regions of the ON-center receptive field in the B channel,***,for nighttime images where infrared information takes precedence,the ON-IR signal and the Visual-enhanced IR signal are separately input into the central excitation and surrounding suppression regions of the ON-center receptive field in the B *** outcome is a pseudo-color fused *** third segment employs five different no-reference image quality assessment methods to evaluate the quality of thirteen sets of pseudo-color images produced by fusing infrared and visible *** images are then compared with those obtained by six other methods cited in the relevant *** empirical results indicate that this study's outcomes surpass the comparative results in terms of average gradient and spatial *** one or two sets of fused images underperformed in terms of standard deviation and entropy when compared to the control *** sets of fused images did not perform as well as the comparison in the QAB/F *** conclusion,the fused images generated through the proposed method show superior performance in terms of scene detail,visual perception,and image sharpness

关键词： Rattlesnake Visible image Infrared image Daylight Bionic

Higher body mass index deteriorates postoperative outcomes of pancreaticoduodenectomy

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Hepatobiliary & Pancreatic Diseases International 2020年第2期19卷 163-168页

作者： Si-Yi zou Wei-Shen Wang Qian zhan Xia-Xing Deng Bai-yong Shen Pancreatic Disease Center Research Institute of Pancreatic DiseaseShanghai Institute of Digestive SurgeryRuijin HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200025China

Background:Previous studies presented controversies in impact of body mass index(BMI)on perioper-ative complications in pancreatectomy,and mainly focused on Western *** study aimed to explore the impact of BMI on perioperative outcomes in Chinese patients undergoing ***:Seven hundred and seven adult patients undergoing open pancreaticoduodenectomy between January 2005 and December 2016 at Ruijin Hospital were studied retrospectively and categorized as obese(BMI≥25 kg/m^2),overweight(BMI≥23 kg/m^2 and<25 kg/m^2),or normal weight(BMI≥18.5 kg/m^2 and<23 kg/m^2).Associations of these BMI groups with perioperative outcomes were ***:The overweight and obese groups experienced higher risk of clinically related postoperative pan-creatic fistula(CR-POPF)(7.6%vs.9.9%vs.17.6%,P=0.002)and re-operation(1.1%vs.2.5%vs.5.1%,P=0.017),and longer systemic inflammation response syndrome(SIRS)duration[2(1–9)d vs.2(1–7)d vs.3(1–10)d,P=0.003]and postoperative hospital stay[19(2–84)d vs.19(7–158)d vs.23(8–121)d,P=0.023]than the normal weight group *** multiple logistic regression models showed obese as an independent risk factor for CR-POPF(P=0.013).The multiple linear regression analysis confirmed BMI as a predictor for prolonged postoperative hospital stay(P=0.005).Conclusions:Higher BMI results in higher morbidity of Chinese patients undergoing open *** is still a safe surgery procedure for overweight and obese patients,with intensive perioperative management.

关键词： Body mass index Obesity Overweight Pancreaticoduodenectomy

Changes of Antioxidative Enzymes and Lipid Peroxidation in Leaves and Roots of Waterlogging-Tolerant and Waterlogging-Sensitive Maize Genotypes at Seedling Stage

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Agricultural Sciences in China 2010年第5期9卷 651-661页

作者： TANG Bin XU Shang-zhong zou Xi-ling ZHENG yong-lian QIU Fa-zhan National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University Wuhan 430070 P.R.China

To better understand the physiological and biochemical mechanisms of waterlogging tolerance, waterlogging effects on lipid peroxidation and the activity of antioxidative enzymes were investigated in leaves and roots of two maize genotypes, HZ32 （waterlogging-tolerant） and K12 （waterlogging-sensitive）. Potted maize plants were waterlogged at the second leaf stage under glasshouse conditions. Leaves and roots were harvested 1 d before and 2, 4, 6, 8 and 10 d after the start of waterlogging treatment. Through comparing the activities of superoxide dismutase （SOD）, ascorbate peroxidase （APX）, glutathione reductase （GR）, catalase （CAT） and guaiacol peroxidase （POD） between waterlogging-tolerant and waterloggingsensitive genotype, we deduced that CAT was the most important H2O2 scavenging enzyme in leaves, while APX seemed to play a key role in roots. POD, APX, GR and CAT activities in conjunction with SOD seem to play an essential protective role in the O2^- and H2O2 scavenging process. Lipid peroxidation was enhanced significantly only in K12 （P 〈 0.001） and there was no difference （P 〉 0.05） in HZ32 up to 6 d after waterlogging stress. These results indicated that oxidative stress may play an important role in waterlogging-stressed maize plants and that the greater protection of HZ32 leaves and roots from waterlogging-induced oxidative damage results, at least in part, through the maintenance of increased antioxidant enzyme activity.

关键词： antioxidative enzymes lipid peroxidation maize (Zea mays L.) seedling stage waterlogging stress

Stronger Version Sensitivity, Almost Finite to One Extension and Maximal Pattern Entropy

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Communications in Mathematics and Statistics 2017年第2期5卷 123-139页

作者： yong zou School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026AnhuiChina

In this paper,we introduce thickr-sensitivity,multi-r-sensitivity and block thick r-sensitivity for r≥*** first give a characterization of a minimal system which is block thickly *** we obtain a sufficient condition of a minimal system which is thickly *** maximal pattern entropy of a multi-r-sensitive topological dynamical system is also discussed.

关键词： Sensitivity Minimal system Almost finite to one extension Maximal type entropy

Electromagnetic Characteristic of Twin-wire Indirect Arc Welding

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 123-131页

作者： SHI Chuanwei zou yong zou Zengda WU Dongting Key Laboratory of Liquid Structure and Heredity of Materials Shandong University

Traditional welding methods are limited in low heat input to workpiece and high welding wire melting rate. Twin-wire indirect arc（TWIA） welding is a new welding method characterized by high melting rate and low heat input. This method uses two wires one connected to the negative electrode and another to the positive electrode of a direct-current（DC） power source. The workpiece is an independent, non-connected unit. A three dimensional finite element model of TWIA is devised. Electric and magnetic fields are calculated and their influence upon TWIA behavior and the welding process is discussed. The results show that with a 100 A welding current, the maximum temperature reached is 17 758 K, arc voltage is 14.646 V while maximum current density was 61 A/mm2 with a maximum Lorene force of 84.5 ~tN. The above mentioned arc parameters near the cathode and anode regions are far higher than those in the arc column region. The Lorene force is the key reason for plasma velocity direction deviated and charged particles flowed in the channel formed by the cathode, anode and upper part of arc column regions. This led to most of the energy being supplied to the polar and upper part of arc column regions. The interaction between electric and magnetic fields is a major determinant in shaping TWIA as well as heat input on the workpiece. This is a first study of electromagnetic characteristics and their influences in the TWIA welding process, and it is significant in both a theoretical and practical sense.

关键词： twin-wire indirect arc welding electromagnetic simulation

Pricing the spare bandwidth: towards maximizing data center's profit

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Science China(Information Sciences) 2016年第10期59卷 50-59页

作者： yong zhan Du XU Hongfang YU School of Communication & Information Engineering University of Electronic Science and Technology of China

To provide tenants with predictable network performance, tenants are allowed to purchase specified amount of data center network(DCN) resources(e.g., bandwidth). Then, data center will reserve the purchased resources for the corresponding tenants. Meanwhile, some DCNs are work conserving, which means that the spare bandwidth will be fairly shared by all active tenants. Even though the amount of the spare bandwidth is stochastic and uncertain, DCN providers are not likely to give away it for free. Thus, data center with work conserving may impose extra payment on tenants for using the spare bandwidth. In this paper, we propose a suitable tariff to charge for the usages of DCN resources, which includes a bill for the usage of the spare bandwidth. Through theoretical analysis and simulation, we demonstrate that our tariff can incentivize tenants to adjust their purchases of bandwidths, which can lead to the improvement of data center's profit by 27.4%without impairing the social welfare.

关键词： spare bandwidth data center network(DCN) bandwidth reservation work conserving pricing/tariff

Influence of nanosized magnesia on the hydration of borehole-sealing cements prepared using different methods

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International Journal of Coal Science & Technology 2023年第4期10卷 343-360页

作者： Quanle zou Jinfei zhan Xin Wang Zhen Huang State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing 400044China

Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas *** expansibilities of cement pastes used in borehole-sealing processes are critical for the borehole-sealing *** magnesia expansive agents are used to improve the expansibilities of cement pastes and improve the borehole-sealing *** magnetic resonance spectrometry and scanning electron microscopy were adopted to study the efects of nanosized magnesia on the hydration of borehole-sealing cements used with diferent preparation *** results showed that an increase in the mass fraction of the nanosized magnesia promoted cement hydration,and the mass fraction was positively correlated with the promotion *** use of diferent preparation methods did not change the water-phase distribution in the *** using the wet-mixing preparation method,nanosized magnesia promoted the induction,acceleration,and deceleration periods of hydration;when using the dry-mixing preparation method,the nanosized magnesia promoted the induction period of cement hydration,and the promotion efect was less obvious than that seen when using the wet-mixing *** using the wet-mixing preparation method,the nanosized magnesia was uniformly dispersed,thus enlarging the surface area of the reaction,which provided more nucleation sites for the hydration products of the cement and therefore accelerated the hydration *** using the dry-mixing preparation method,the nanosized magnesia powders were dispersed nonuniformly and *** these conditions,only a few nanosized magnesia particles on the surfaces of the aggregated clusters took part in hydration,so only a small number of nucleation sites were provided for the hydration products of *** led to inconsistent hydration of cement pastes prepared using the dry-mixing *** surface porosity of the cement prepared with the wet-mi

关键词： Borehole-sealing cement Nanosized magnesia Preparation method Hydration Morphological analysis Nuclear magnetic resonance relaxation analysis

Interfacial Bonding Mechanism and Mechanical Performance of Continuous Fiber Reinforced Composites in Additive Manufacturing

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Chinese Journal of Mechanical Engineering 2021年第1期34卷 131-141页

作者： Congze Fan Zhongde Shan Guisheng zou Li zhan Dongdong Yan State Key Laboratory of Advanced Forming Technology and Equipment Beijing 100044China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Nanjing University of Aeronautics and Astron autics Nanjing 210016China China Academy of Mach inery Science&Technology Group Co. Ltd.Beijing 100044China

The additive manufacturing of continuous fiber composites has the advantage of a high-precision and efficient forming process,which can realize the lightweight and integrated manufacturing of complex ***,many void defects exist between layers in the printing process of additive manufacturing;consequently,the bonding performance between layers is *** bonding neck is considered a key parameter for representing the quality of interfacial *** this study,the formation mechanism of the bonding neck was comprehensively ***,the influence of the nozzle and basement temperatures on the printing performance and bonding neck size was ***,CT scanning was used to realize the quantitative characterization of bonding neck parameters,and the reason behind the deviation of actual measurements from theoretical calculations was *** the nozzle temperature increased from 180 to 220℃,CT measurement showed that the bonding neck diameter increased from 0.29 to 0.34 mm,and the cross-sectional porosity reduced from 5.48%to 3.22%.Finally,the fracture mechanism was studied,and the influence of the interfacial bonding quality on the destruction process of the materials was *** conclusion,this study can assist in optimizing the process parameters,which improves the precision of the printing parts and performance between the layers.

关键词： 3D printing Thermoplastic resin Continuous fiber Additive manufacturing