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Radiation Hydrodynamic Simulations in the Planar Scheme for the Fundamental Studies of Shock Ignition

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Plasma Science and Technology 2016年第4期18卷 376-381页

作者：董云松杨家敏宋天明朱托黄成武 Department of experimental Physics Laser Fusion Research Center

As a fundamental and crucial research topic in the direct-driven inertial confinement fusion（ICF）,especially for shock ignition（SI）,investigation on the laser coupling with planar lowZ targets is beneficial for deep physical comprehension at the primary phase of *** production of the intense shock and the shock coalescence in the multi-layer targets,driven by the 3ω intense laser（351 nm the wavelength）,were studied in detail with the 1D and 2D radiation hydrodynamic *** was inferred that the 1D simulation would overrate the shock velocity and the ablation pressure of the spike;the coalescence time and the velocity of the coalescence shock depended evidently on the pulse shape and the start time of the *** present study can also provide a semi-quantitative reference for the design of the SI decomposition experiments on the Shenguang-III prototype laser facility.

关键词： shock ignition planar scheme radiation hydrodynamic simulation

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China Life Sciences 2025年第1期 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng Yan Kun Jiang Bingbing Song He Li Maomao Cao Dianqin Sun Fan Yang Xinxin Yan Shaoli Zhang Yi Teng Qianru Li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute Linzhou Cancer Hospital center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan center for Disease Control and Prevention Office for Cancer Control and research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrendstudy provides evidence on supplementing current guideline recommendations.

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experimental and Modeling study of Forest Fire Effect on Soil Thermal Conductivity

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Pedosphere 2016年第4期26卷 462-473页

作者： Kathleen M.SMITS Elizabeth KIRBY William J.MASSMAN Larry Scott BAGGETT center for the experimental study of Subsurface Environmental Processes Department of Civil and Environmental EngineeringColorado School of Mines USDA Forest Service Rocky Mountain Research Station

An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited. The purpose of this study was to evaluate the long-term impact of fire on the effective thermal conductivity of soils by directly comparing fire-heated and no-fire control soils through a series of laboratory studies. The thermal conductivity was measured for ten soil samples from two sites within the Manitou experimental Forest, Colorado, USA, for a range of water contents from saturation to the residual degree of saturation. The thermal conductivity measured was compared with independent estimates made using three empirical models from literature, including the Campbell et al. （1994）, CSt~ and Konrad （2005）, and Massman et al. （2008） models. Results demonstrate that for the test soils studied, the thermal conductivity of the fire-heated soils was slightly lower than that of the control soils for all observed water contents. Modeling results show that the Campbell et al. （1994） model gave the best agreement over the full range of water contents when proper fitting parameters were employed. Further studies are needed to evaluate the significance of including the influence of fire burn on the thermal properties of soils in modeling studies.

关键词： controlled burn degree of saturation empirical model water content wildfire

Small heat shock protein B8:from cell functions to its involvement in diseases and potential therapeutic applications

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Neural Regeneration research 2025年第10期20卷 2872-2886页

作者： Marta Chierichetti Riccardo Cristofani Valeria Crippa Veronica Ferrari Marta Cozzi Elena Casarotto Paola Pramaggiore Laura Cornaggia Guglielmo Patelli Ali Mohamed Margherita Piccolella Mariarita Galbiati Paola Rusmini Barbara Tedesco Angelo Poletti Laboratory of experimental Biology Dipartimento di Scienze Farmacologiche e Biomolecolari“Rodolfo Paoletti”(DiSFeB)Universitàdegli Studi di MilanoMilanItaly

Heat shock protein family B(small)member 8(HSPB8)is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock ***8 is involved in various cellular mechanisms mainly related to proteotoxic stress response and in other processes such as inflammation,cell division,and ***8 binds misfolded clients to prevent their aggregation by assisting protein refolding or degradation through chaperone-assisted selective *** line with this function,the pro-degradative activity of HSPB8 has been found protective in several neurodegenerative and neuromuscular diseases characterized by protein misfolding and *** cancer,HSPB8 has a dual role being capable of exerting either a pro-or an anti-tumoral activity depending on the pathways and factors expressed by the model of cancer under ***,HSPB8 exerts a protective function in different diseases by modulating the inflammatory response,which characterizes not only neurodegenerative diseases,but also other chronic or acute conditions affecting the nervous system,such as multiple sclerosis and intracerebellar *** note,HSPB8 modulation may represent a therapeutic approach in other neurological conditions that develop as a secondary consequence of other *** is the case of cognitive impairment related to diabetes mellitus,in which HSPB8 exerts a protective activity by assuring mitochondrial *** review aims to summarize the diverse and multiple functions of HSPB8 in different pathological conditions,focusing on the beneficial effects of its ***-based and alternative therapeutic approaches targeting HSPB8 and its regulated pathways will be discussed,emphasizing how new strategies for cell and tissue-specific delivery represent an avenue to advance in disease treatments.

关键词： aggregation autophagy cancer chaperone chaperone-assisted selective autophagy cognitive impairment HSPB8 neuroinflammation neuromuscular diseases therapy

High-precision Thickness Setting Models for Titanium Alloy Plate Cold Rolling without Tension

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Chinese Journal of Mechanical Engineering 2015年第2期28卷 422-429页

作者： WANG Xiaochen YANG Quan HE Fei SUN Youzhao XIAO Huifang National Engineering research center of Flat Rolling equipment University of Science and Technology Beijing

Due to its highly favorable physical and chemical properties,titanium and titanium alloy are widely used in a variety of *** of the low output of a single batch,plate cold rolling without tension is the most common rolling production method for titanium *** method is lack of on-line thickness closed-loop control,with carefully thickness setting models for precision.A set of high-precision thickness setting models are proposed to suit the production *** of frequent variations in rolling specification,a model structural for the combination of analytical models and statistical models is adopted to replace the traditional self-learning *** deformation resistance and friction factor,the primary factors which affect model precision,are considered as the objectives of statistical ***,the coefficient fitting of deformation resistance analytical model based on over-determined equations set is ***,a support vector machine（SVM）is applied to the modeling of the deformation resistance and friction *** setting models are applied to a 1450 plate-coiling mill for titanium alloy plate rolling,and then thickness precision is found consistently to be within 3%,exceeding the precision of traditional setting models with a self-learning method based on a large number of stable rolling *** application performance is *** proposed research provides a set of high-precision thickness setting models which are well adapted to the characteristics of titanium alloy plate cold rolling without tension.

关键词： titanium alloy cold rolling deformation resistance friction factor support vector machine

Comparison of up ladder type and terraced type normalizing heat treatments of heavy cylinder

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Journal of Central South University 2016年第11期23卷 2777-2783页

作者：孙建亮彭艳邱丑武张永振 National Engineering research center for equipment and Technology of Cold Strip Rolling Yanshan University

Because of the mixed grain and coarse grain structure, the long heat treatment cycle and large energy conservation in the heavy cylinder heat treatment process, the up ladder type and terraced type normalizing heat treatment of heavy cylinder after rolling were put forward. The microstructure and mechanical properties of 2.25Cr1Mo0.25 V steel after the up ladder type normalizing, terraced type normalizing and isothermal type normalizing were studied. experimental results show that： 1） For the grain refinement, the twice terraced type normalizing is better than the up ladder type and isothermal type normalizing, and the average grain size is 18 μm; 2） The yield strength, tensile strength and-30℃ charpy impact energy after twice terraced type normalizing are 681 MPa, 768 MPa and 181 J, respectively, and the mechanical properties are better than those of the up ladder type and isothermal type normalizing; 3） Compared with the isothermal type normalizing, the holding time of terraced type normalizing can be shortened by 30%, which greatly reduces the energy consumption.

关键词： heavy cylinder terraced type normalizing up ladder type normalizing mechanical properties

Hydrophilic characteristics of soft rock in deep mines

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International Journal of Mining Science and Technology 2015年第2期25卷 177-183页

作者： Guo Hongyun Li Bing Zhang Yumei Wang Xinbo Zhang Feng The Engineering Design research Institute of equipment of PLA Astronaut center of China

A series of water absorption tests on dried soft rock have been conducted by the intelligent testing system for water absorption tests in deep soft rock, including tests of water absorption with and without pres- sure. The results show that the water absorbing capacity of rock with a certain pressure is larger than that of rock without pressure： however, the relationship between the water absorbing percentage and the time can be expressed by w（t） = a（l - e^-bt）. In hi-logarithmic coordinates, the hydrophilic relationship with time in tests with pressure could be characterized by linearity, while they present concave or convex in tests without pressure. Based on the hypothesis that each influential factor is irrelevant and they have a linear correlation with the water absorbing capacity, we calculated the weight coefficient of each factor according to experimental results under different conditions. The calculations demonstrate that the effec- tive porosity, content of smectite and kaolinite are all positively correlated with the water absorption capacity of rock; meanwhile, the fractal dimension of the effective pores presents a negative correlation with the water absorption capacity of rock. The water absorption capacity with pressure increases with increasing illite, chlorite and chlorite/smectite formation and a decrease in illite/smectite formation and the fractal dimension of the effective pores, while it is opposite in tests without pressure. The weight coefficient of smectite is smallest among positive factors, and the fractal dimension of the effective pores is the smallest amongst the negative factors.

关键词： Deep soft rock Water absorption tests Porosity Fractal dimension Clay minerals

Design and test of tray-seedling sorting transplanter

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International Journal of Agricultural and Biological Engineering 2015年第2期8卷 14-20页

作者： Feng Qingchun Zhao Chunjiang Jiang Kai Fan Pengfei Wang Xiu Beijing research center of Intelligent equipment for Agriculture Beijing 100097China

In order to improve the automatic sorting and transplanting of tray-seedling and reduce labors strength,a new sorting transplanter was *** to the feature of normal seedling tray and manual grading method,the mechanical sorting procedure was *** key parts of sorting transplanter are as follows:an efficient transfer mechanism with aerodynamic buffer,a seedling identifying and measuring unit based on linear-structured vision,the extendible multi-grasper with wireless technology and the system *** experiments were conducted and showed that the transplanting success rate was 90.0% on the tray of 6×12 holes under the speed of 700 cycles per *** vision unit’s failed identifying rate for the superior pepper seedlings on five different trays was less than 10%,and the measurement error of seedling height was about 5 mm.

关键词： transplanter tray seedling sorting grasper machine vision wireless technology

Investigation of CFD Calculation Method of a Centrifugal Pump with Unshrouded Impeller

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 376-384页

作者： WU Dazhuan YANG Shuai XU Binjie LIU Qiaoling WU Peng WANG Leqin Institute of Process equipment Zhejiang University Engineering research center of High Pressure Process equipment and Safety of Ministry of Education Zhejiang University

Currently, relatively large errors are found in numerical results in some low-specific-speed centrifugal pumps with unshrouded impeller because the effect of clearances and holes are not accurately modeled. Establishing an accurate analytical model to improve performance prediction accuracy is therefore necessary. In this paper, a three-dimensional numerical simulation is conducted to predict the performance of a low-specific-speed centrifugal pump, and the modeling, numerical scheme, and turbulent selection methods are discussed. The pump performance is tested in a model pump test bench, and flow rate, head, power and efficiency of the pump are obtained. The effect of taking into consideration the back-out vane passage, clearance, and balance holes is analyzed by comparing it with experimental results, and the performance prediction methods are validated by experiments. The analysis results show that the pump performance can be accurately predicted by the improved method. Ignoring the back-out vane passage in the calculation model of unshrouded impeller is found to generate better numerical results. Further, the calculation model with the clearances and balance holes can obviously enhance the numerical accuracy. The application of disconnect interface can reduce meshing difficulty but increase the calculation error at the off-design operating point at the same time. Compared with the standard k-ε, renormalization group k-ε, and Spalart-Allmars models, the Realizable k-ε model demonstrates the fastest convergent speed and the highest precision for the unshrouded impeller flow simulation. The proposed modeling and numerical simulation methods can improve the performance prediction accuracy of the low-specific-speed centrifugal pumps, and the modeling method is especially suitable for the centrifugal pump with unshrouded impeller.

关键词： centrifugal pump unshrouded impeller numerical simulation clearance turbulence model