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Preoperative controlling nutritional status as an optimal prognostic nutritional index to predict the outcome for colorectal cancer 被引量:1
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作者 Li-Xiang Liu Hao Wang +6 位作者 Bo Gao Ting-Ting Xu Qing-Gang Yuan Shi-Zhen Zhou Chao Ding Ji Miao Wen-Xian Guan 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期343-353,共11页
BACKGROUND The controlling nutritional status(CONUT)score effectively reflects a patient’s nutritional status,which is closely related to cancer prognosis.This study invest-igated the relationship between the CONUT s... BACKGROUND The controlling nutritional status(CONUT)score effectively reflects a patient’s nutritional status,which is closely related to cancer prognosis.This study invest-igated the relationship between the CONUT score and prognosis after radical surgery for colorectal cancer,and compared the predictive ability of the CONUT score with other indexes.AIM To analyze the predictive performance of the CONUT score for the survival rate of colorectal cancer patients who underwent potentially curative resection.METHODS This retrospective analysis included 217 patients with newly diagnosed colorectal.The CONUT score was calculated based on the serum albumin level,total lymphocyte count,and total cholesterol level.The cutoff value of the CONUT score for predicting prognosis was 4 according to the Youden Index by the receiver operating characteristic curve.The associations between the CONUT score and the prognosis were performed using Kaplan-Meier curves and Cox regression analysis.RESULTS Using the cutoff value of the CONUT score,patients were stratified into CONUT low(n=189)and CONUT high groups(n=28).The CONUT high group had worse overall survival(OS)(P=0.013)and relapse-free survival(RFS)(P=0.015).The predictive performance of CONUT was superior to the modified Glasgow prognostic score,the prognostic nutritional index,and the neutrophil-to-lymphocyte ratio.Meanwhile,the predictive performances of CONUT+tumor node metastasis(TNM)stage for 3-year OS[area under the receiver operating characteristics curve(AUC)=0.803]and 3-year RFS(AUC=0.752)were no less than skeletal muscle mass index(SMI)+TNM stage.The CONUT score was negatively correlated with SMI(P<0.01).CONCLUSION As a nutritional indicator,the CONUT score could predict long-term outcomes after radical surgery for colorectal cancer,and its predictive ability was superior to other indexes.The correlation between the CONUT score and skeletal muscle may be one of the factors that play a predictive role. 展开更多
关键词 controlling nutritional status Colorectal cancer Prognostic marker SARCOPENIA Skeletal muscle
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Real-Time Co-optimization of Gear Shifting and Engine Torque for Predictive Cruise Control of Heavy-Duty Trucks
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作者 Hongqing Chu Xiaoxiang Na +4 位作者 Huan Liu Yuhai Wang Zhuo Yang Lin Zhang Hong Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期294-317,共24页
Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a rea... Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty trucks.To minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is used.Finding the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method.Dynamic programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed solver.Simulation,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller.The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing roads.Moreover,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time. 展开更多
关键词 Heavy-duty truck Predictive cruise control Model predictive control Pontryagin’s maximum principle Real-truck implementation
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Controlling the dynamic behavior of decentralized cluster through centralized approaches
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作者 袁大明 王培龙 +6 位作者 王鹏 马星宇 汪楚云 王璟 陈怀城 王高 叶方富 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期46-54,共9页
How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation... How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems. 展开更多
关键词 self-organizing system centralized control dynamics regulation
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Gypsum-based Silica Gel Humidity-controlling Composite Materials:Preparation,Characterization,and Performance
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作者 李曦 冉茂宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期337-344,共8页
Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based compos... Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based composites were compared with adding different silica gel particle size and proportion.The morphological characteristics,the isothermal equilibrium moisture content curve,moisture absorption and desorption rate,moisture absorption and desorption stability,and humidity-conditioning performance were tested and analyzed.The experimental results show that,compared with pure-gypsum,the surface structure of the gypsum-based composites is relatively loose,the quantity,density and aperture of the pores in the structure increase.The absorption and desorption capacity increase along with the increase of silica gel particle size and silica gel proportion.When 3 mm silica gel particle size is added with a mass ratio of 40%,the maximum equilibrium moisture content of humidity-controlling composites is 0.161 g/g at 98% relative humidity(RH),3.22 times that of pure-gypsum.The moisture absorption and desorption rates are increased,the equilibrium moisture absorption and desorption rates are 2.68 times and 1.61 times that of pure-gypsum at 58.5% RH,respectively.The gypsum-based composites have a good stability,which has better timely response to dynamic humidity changes and can effectively regulate indoor humidity under natural conditions. 展开更多
关键词 humidity controlling composite materials GYPSUM silica gel
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES Development characteristics controlling factors Shale oil Sweet spot
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Controlling Reactivity of Palladium Amides for Selective Carbonylation towards Urea and Oxamide Derivatives
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作者 WANG Jin-hui CAO Yan-wei HE Lin 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期297-308,共12页
Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.... Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.Herein,our study introduces a strategy employing palladium amides,harnessing their unique reactivity control,to direct the selective carbonylation of amines for the targeted synthesis of urea and oxamide derivatives.The palladium amide structure was elucidated using single-crystal X-ray diffraction.Controlled experiments and cyclic voltammetry studies further elucidate that the oxidation of palladium amide or its insertion into a carbonyl group diverges into distinct pathways.By employing sodium percarbonate as an eco-friendly oxidant and base,we have successfully constructed a switchable carbonylation system co-catalyzed by palladium and iodide under room temperature.The utilizing strategy in this study not only facilitates effective control over reaction selectivity but also mitigates the risk of explosions,a critical safety concern in traditional carbonylation methods. 展开更多
关键词 selectivity control palladium catalysis oxidative carbonylation AMINOCARBONYLATION green reagents
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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China
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作者 Gang Li Xian-Ming Xiao +3 位作者 Bo-Wei Cheng Chen-Gang Lu Yue Feng Dong-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1488-1507,共20页
The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not w... The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well understood.In the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed.The results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM pores.The pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,respectively.The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,respectively.Compared with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption capacity.The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas potential.Considering the geological and geochemical conditions of shale gas formation and preservation,the deep-water shelf facies is the most favorable target for the Lower Cambrian shale gas exploration and development in the western Hubei area,South China. 展开更多
关键词 Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content controlling factor
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Spatial-temporal heterogeneity and controlling factors of evapotranspiration in Nujiang River Basin based on Variable Infiltration Capacity(VIC)model
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作者 ZHANG Xianhe LIU Shiyin +1 位作者 ZHU Yu XIE Fuming 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3598-3614,共17页
Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by la... Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw). 展开更多
关键词 EVAPOTRANSPIRATION Variable infiltration capacity(VIC)model Spatial temporal heterogeneity Climate change controlling factors Nujiang River Basin
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Numerical Study of Co-flow Jet Control on Corner Separation in Compressor Cascade
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作者 Rui-ling Xu Tong-xi Li +1 位作者 Zhi-heng Wang Guang Xi 《风机技术》 2024年第5期25-33,共9页
The design objectives of modern aircraft engines include high load capacity,efficiency,and stability.With increasing loads,the phenomenon of corner separation in compressors intensifies,affecting engine performance an... The design objectives of modern aircraft engines include high load capacity,efficiency,and stability.With increasing loads,the phenomenon of corner separation in compressors intensifies,affecting engine performance and stability.Therefore,the adoption of appropriate flow control technology holds significant academic and engineering significance.This study employs the Reynolds-averaged Navier-Stokes(RANS)method to investigate the effects and mechanisms of active/passive Co-flow Jet(CFJ)control,implemented by introducing full-height and partial height jet slots between the suction surface and end wall of a compressor cascade.The results indicate that passive CFJ control significantly reduces the impact of corner separation at small incidence,with partial-height control further enhancing the effectiveness.The introduction of active CFJ enables separation control at large incidence,improving blade performance under different operating conditions.Active control achieves this by reducing the scale of corner separation vortices,effectively reducing the size of the separation region and enhancing blade performance. 展开更多
关键词 Compressor Cascade co-flow Jet control Corner Separation Loss Analysis Vortex Structure Analysi
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Enrichment model and major controlling factors of below-source tight oil in Lower Cretaceous Fuyu reservoirs in northern Songliao Basin,NE China
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作者 WANG Xiaojun BAI Xuefeng +9 位作者 LI Junhui JIN Zhijun WANG Guiwen CHEN Fangju ZHENG Qiang HOU Yanping YANG Qingjie LI Jie LI Junwen CAI Yu 《Petroleum Exploration and Development》 SCIE 2024年第2期279-291,共13页
Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics... Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics,the tight oil enrichment model and its major controlling factors.First,the Quantou Formation is overlaid by high-quality source rocks of the Upper Cretaceous Qingshankou Formation,with the development of nose structure around sag and the broad and continuous distribution of sand bodies.The reservoirs are tight on the whole.Second,the configuration of multiple elements,such as high-quality source rocks,reservoir rocks,fault,overpressure and structure,controls the tight oil enrichment in the Fuyu reservoirs.The source-reservoir combination controls the tight oil distribution pattern.The pressure difference between source and reservoir drives the charging of tight oil.The fault-sandbody transport system determines the migration and accumulation of oil and gas.The positive structure is the favorable place for tight oil enrichment,and the fault-horst zone is the key part of syncline area for tight oil exploration.Third,based on the source-reservoir relationship,transport mode,accumulation dynamics and other elements,three tight oil enrichment models are recognized in the Fuyu reservoirs:(1)vertical or lateral migration of hydrocarbon from source rocks to adjacent reservoir rocks,that is,driven by overpressure,hydrocarbon generated is migrated vertically or laterally to and accumulates in the adjacent reservoir rocks;(2)transport of hydrocarbon through faults between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downward through faults to the sandbodies that are separated from the source rocks;and(3)migration of hydrocarbon through faults and sandbodies between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downwards through faults to the reservoir rocks that are separated from the source rocks,and then migrates laterally through sandbodies.Fourth,the differences in oil source conditions,charging drive,fault distribution,sandbody and reservoir physical properties cause the differential enrichment of tight oil in the Fuyu reservoirs.Comprehensive analysis suggests that the Fuyu reservoir in the Qijia-Gulong Sag has good conditions for tight oil enrichment and has been less explored,and it is an important new zone for tight oil exploration in the future. 展开更多
关键词 northern Songliao Basin Cretaceous Quantou Formation Qingshankou Formation upper generation and lower storage Fuyu reservoir tight oil main control factor enrichment model
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Treatment of Coronary Heart Disease from the Perspective of Liver Controlling Dispersion
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作者 Lijun Zhang Jingyun Sun +1 位作者 Tingting He Yalin Qian 《Journal of Clinical and Nursing Research》 2024年第2期158-164,共7页
The liver is in charge of distributing and regulating the movement of qi throughout the whole body,coordinating the transportation and transformation of the internal organs in the middle part of the body,promoting the... The liver is in charge of distributing and regulating the movement of qi throughout the whole body,coordinating the transportation and transformation of the internal organs in the middle part of the body,promoting the biochemical circulation of qi,blood,and body fluids,and regulating emotions.Liver dysfunction can disrupt the transportation and transformation of qi,blood,and body fluids,causing phlegm turbidity,blood stasis,and other unwanted symptoms.Poor regulation of emotion further aggravates the accumulation of pathological substances,resulting in the obstruction of heart vessels,and ultimately coronary heart disease(CHD).Through regulating lipid metabolism,inflammatory reaction,vasoactive substances,platelet function,neuroendocrine,and other factors,liver controlling dispersing qi plays a comprehensive role in the prognosis of atherosclerosis,the primary cause of CHD.Therefore,it is recommended to treat CHD from the perspective of liver-controlling dispersion. 展开更多
关键词 Liver controlling dispersion Coronary atherosclerotic heart disease ATHEROSCLEROSIS Traditional chinese medicine TREATMENT
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镁合金表面热喷涂WC-10Co-4Cr粒子沉积及分布特性 被引量:1
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作者 方敏 蒋理帅祎 +1 位作者 刘富强 张治民 《科学技术与工程》 北大核心 2024年第8期3186-3192,共7页
为了探究高速空气燃料热喷涂(activated combustion-high velocity air fuel,AC-HVAF)过程中喷涂粒子撞击基材后的沉积特性。采用AC-HVAF热喷涂技术在AZ80镁合金基体上沉积WC-10Co-4Cr硬质涂层。通过离散沉积实验获得薄层沉积粒子,探讨... 为了探究高速空气燃料热喷涂(activated combustion-high velocity air fuel,AC-HVAF)过程中喷涂粒子撞击基材后的沉积特性。采用AC-HVAF热喷涂技术在AZ80镁合金基体上沉积WC-10Co-4Cr硬质涂层。通过离散沉积实验获得薄层沉积粒子,探讨各种沉积形貌的种类、形成原因、结合机制及射流中粒子的径向和轴向分布。结果表明:在AC-HVAF粒子沉积过程中,嵌入型沉积为主要的沉积形貌,同时包含少量的破碎型与空腔型沉积粒子。在涂层的形成过程中,嵌入型沉积对涂层/基体结合性能起重要作用;空腔型沉积的小颗粒及破碎型沉积的大颗粒是造成沉积效率下降的主要原因。喷涂粒子主要集中在射流中心,越靠近射流边缘,空腔型沉积粒子越多,最终导致AC-HVAF粒子射流呈现出空间分布特征。 展开更多
关键词 超音速火焰喷涂 WC-10co-4Cr 沉积状态 粒子射流 镁合金
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平菇^(60)Co-γ诱变孢子杂交新种质的创制及其遗传多样性分析
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作者 龚娜 刘国丽 +3 位作者 陈珣 马晓颖 肇莹 肖军 《核农学报》 CAS CSCD 北大核心 2024年第11期2047-2053,共7页
为了探究不同平菇品种对辐射的敏感性及适宜辐射剂量,以便快速准确地鉴别平菇的杂交后代,创制新平菇种质,从而加快育种进程,本研究利用10个^(60)Co-γ射线剂量分别辐射4种不同平菇的孢子悬浮液,对致死率进行统计,并获得了诱变菌株的孢... 为了探究不同平菇品种对辐射的敏感性及适宜辐射剂量,以便快速准确地鉴别平菇的杂交后代,创制新平菇种质,从而加快育种进程,本研究利用10个^(60)Co-γ射线剂量分别辐射4种不同平菇的孢子悬浮液,对致死率进行统计,并获得了诱变菌株的孢子单核体。随后配制杂交组合,开展了^(60)Co-γ诱变和杂交育种研究。基于简单序列重复(SSR)标记,对诱变后材料和杂交后代共39份材料进行了遗传多样性分析。结果表明,品种5178的适宜辐射剂量为500 Gy,时间为200 min;9408的适宜辐射剂量为600 Gy,时间为240 min;灰美2号的适宜辐射剂量为700 Gy,时间为280 min;榆黄菇T2的适宜辐射剂量为400 Gy,时间为160 min。筛选获得的35个长势良好的杂交子中,经SSR分子标记验证,这些菌株在8对引物扩增下呈现出不同的特异性条带。综上,本研究可快速、准确地鉴别杂交子,为平菇的辐射诱变和杂交育种提供了技术依据和理论参考。 展开更多
关键词 平菇 ^(60)co-γ诱变 致死率 拮抗反应 SSR
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^(60)Co-γ射线对不同无花果品种一年生枝条的辐射效应分析
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作者 巴哈依丁·吾甫尔 阿布来克·尼牙孜 +3 位作者 胡西旦·买买提 吕小龙 王浩淼 马会勤 《新疆农业科学》 CAS CSCD 北大核心 2024年第2期373-381,共9页
【目的】研究^(60)Co-γ射线对不同无花果品种一年生枝条死亡率、抗氧化酶活性等相关理化指标的影响,确定最佳辐射诱变剂量,为利用^(60)Co-γ射线辐射诱变技术提高无花果遗传多样性、创造新种质、培育优良新品种提供科学依据。【方法】... 【目的】研究^(60)Co-γ射线对不同无花果品种一年生枝条死亡率、抗氧化酶活性等相关理化指标的影响,确定最佳辐射诱变剂量,为利用^(60)Co-γ射线辐射诱变技术提高无花果遗传多样性、创造新种质、培育优良新品种提供科学依据。【方法】以无花果品种布兰瑞克和中华紫果一年生休眠枝为试材,采用^(60)Co-γ射线为辐照源,设置不同剂量0、30、45、60、75 Gy的辐射处理,分析辐照引起枝叶死亡率、酶活性等变化。【结果】随着辐射剂量的增加,2个无花果品种扦插苗成活率呈下降趋势,株高、茎粗、节间长度、叶片长度、叶片宽度和分枝数指标呈下降趋势,叶片长宽比差异不显著。中华紫果品种的SOD、POD、CAT等酶活性均呈现先增后减的趋势,分别在45、60 Gy剂量时达到峰值,MDA含量呈现一直上升趋势,H_(2)O_(2)含量呈现先增后降趋势。布兰瑞克品种的SOD、POD、CAT酶活性,随着辐射剂量的增加均呈现先降后增趋势。MDA、H_(2)O_(2)含量基本保持上升趋势。【结论】辐射导致无花果扦插苗幼苗生长缓慢、株高矮化、茎粗变细、叶片变小、分枝减少。中华紫果的半致死辐射剂量为56 Gy,布兰瑞克为70 Gy,布兰瑞克对辐射的耐受性高于中华紫果。 展开更多
关键词 ^(60)co-γ射线 无花果 辐射效应 酶活性
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^(60)Co-γ辐射对2种锦带幼苗生长及生理指标的影响
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作者 张洁 宋佳宝 史宝胜 《林业与生态科学》 2024年第1期94-101,共8页
为了探究辐射诱变对“白花锦带花”和“锦带花”形态及生理特性的影响,采用不同剂量(0~300 Gy)的^(60)Co-γ射线辐射“白花锦带花”与“锦带花”休眠期种子,观测辐射对锦带花生长的影响,测定其生长量及幼苗叶片的叶绿素含量、叶绿素荧... 为了探究辐射诱变对“白花锦带花”和“锦带花”形态及生理特性的影响,采用不同剂量(0~300 Gy)的^(60)Co-γ射线辐射“白花锦带花”与“锦带花”休眠期种子,观测辐射对锦带花生长的影响,测定其生长量及幼苗叶片的叶绿素含量、叶绿素荧光指标、光合作用参数、SOD、POD、MDA和可溶性蛋白含量。研究结果显示,由于辐射剂量的增大,苗高、叶长、叶宽、节间距、叶绿素荧光、光合作用参数、SOD活性、POD活性出现了明显的先升高后降低的趋势,在50 Gy时到达了峰值。同时,随着辐射剂量的增加,叶绿素含量和可溶性蛋白含量呈现出下降的趋势,MDA含量明显升高。综上所述,在(2 Gy/min)剂量率的辐射条件下“白花锦带花”种子较适宜的诱变剂量为50 Gy,而“锦带花”以50~100 Gy最合适。 展开更多
关键词 白花锦带花 锦带花 ^(60)co-γ射线 辐射育种
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不同剂量^(60)Co-γ射线辐照藜麦种子的效应研究
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作者 魏志敏 崔纪菡 +6 位作者 吕玮 赵宇 王京新 赵文庆 裴美燕 刘建军 李顺国 《农业科技通讯》 2024年第4期92-96,共5页
为了研究^(60)Co-γ射线辐照在藜麦育种中的应用,探讨^(60)Co-γ射线辐射诱变藜麦的适宜剂量,本研究利用4种剂量^(60)Co-γ辐射4个不同藜麦品种,对辐射后的种子进行室内发芽试验和田间种植试验,并对M1代的生育过程、畸变率、突变率进行... 为了研究^(60)Co-γ射线辐照在藜麦育种中的应用,探讨^(60)Co-γ射线辐射诱变藜麦的适宜剂量,本研究利用4种剂量^(60)Co-γ辐射4个不同藜麦品种,对辐射后的种子进行室内发芽试验和田间种植试验,并对M1代的生育过程、畸变率、突变率进行了调查和分析。结果表明,经过150~450 Gy的辐照剂量处理后,藜麦的形态特征和生长表现出显著变化;发芽率呈先上升后下降的趋势,150 Gy剂量可促进种胚活力,250 Gy以上剂量显著降低发芽率;辐射导致出苗延迟,高剂量下甚至无法正常出苗,出苗率也显著降低,表明辐射对幼苗生长产生负面影响;成株率随辐射剂量增加而下降,幼苗自然枯死增多,说明辐射对发芽种子胚芽的继续发育抑制显著;辐射导致遗传变异,包括早熟、矮化、穗颜色等方面,突变频率随剂量增加而增加。综上可知,藜麦的生长、发芽、出苗、成株等受到辐射剂量影响,适度辐射可促进发芽,但高剂量对生长和遗传特性产生负面效应。本研究对于辐射育种的可行性和作物改良意义重大,但需深入研究其机制和应用潜力。 展开更多
关键词 藜麦 辐射 育种 ^(60)co-γ
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^(60)Co-γ射线辐照灭菌对牡丹皮质量影响的多元评价研究 被引量:2
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作者 毛腾霄 黄春燕 +4 位作者 伍欣然 张良 陈红 何江 黄敏 《核农学报》 CAS CSCD 北大核心 2024年第4期685-692,共8页
为考察^(60)Co-γ射线辐照灭菌对牡丹皮质量的影响,本研究采用不同吸收剂量(0、5、10、20、30 kGy)^(60)Co-γ射线辐照处理试验样品,比较辐照前后样品微生物负载变化、高效液相色谱(HPLC)指纹图谱相似度、水提物抑菌活性的变化,并建立... 为考察^(60)Co-γ射线辐照灭菌对牡丹皮质量的影响,本研究采用不同吸收剂量(0、5、10、20、30 kGy)^(60)Co-γ射线辐照处理试验样品,比较辐照前后样品微生物负载变化、高效液相色谱(HPLC)指纹图谱相似度、水提物抑菌活性的变化,并建立牡丹皮近红外光谱一致性评价模型。结果表明,当吸收剂量为5 kGy时即可让微生物负载超标样品中的需氧菌总数、霉菌和酵母菌总数及耐胆盐革兰阴性菌数量降至标准规定(《美国药典》USP-NF2023)以下;随着吸收剂量的增加,牡丹皮样品指纹图谱相似度呈下降趋势;辐照后样品水提物对金黄色葡萄球菌的抑菌圈直径与未辐照相比无显著差异(P>0.05);采用近红外光谱一致性评价模型能够较好地区分辐照与未辐照样品。鉴于不适宜的^(60)Co-γ射线辐照剂量可能会对牡丹皮质量造成一定影响,建议牡丹皮的辐照吸收剂量不超过5 kGy。本研究结果可为牡丹皮辐照灭菌吸收剂量的选取提供参考依据。 展开更多
关键词 牡丹皮 ^(60)co-γ辐照 指纹图谱 近红外光谱 抑菌活性
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^(60)Co-γ射线辐照对雪茄烟叶发酵微生物和代谢物变化及烟叶质量的影响 被引量:1
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作者 张蓝月 秦艳青 +3 位作者 赵园园 任梦娟 张瑞娜 史宏志 《中国烟草学报》 CAS CSCD 北大核心 2024年第2期125-134,共10页
【目的】通过^(60)Co-γ射线辐照灭菌,明确微生物在雪茄烟叶发酵过程中的重要作用。【方法】以四川雪茄烟品种德雪1号为试验材料,以剂量10 kGy的^(60)Co-γ射线对发酵前烟叶进行辐照处理,测定分析发酵过程中烟叶微生物多样性、代谢组学... 【目的】通过^(60)Co-γ射线辐照灭菌,明确微生物在雪茄烟叶发酵过程中的重要作用。【方法】以四川雪茄烟品种德雪1号为试验材料,以剂量10 kGy的^(60)Co-γ射线对发酵前烟叶进行辐照处理,测定分析发酵过程中烟叶微生物多样性、代谢组学、中性香气成分和常规化学成分含量。【结果】(1)辐照组烟叶发酵28 d样本经传统分离培养和Illumina MiSeq高通量测序均未发现细菌群落。(2)非靶向代谢组学结果显示,辐照组烟叶发酵28 d后芸香苷、根皮苷和山奈酚等多酚类物质,山奈酚-3-O-芸香糖苷等多酚糖苷类物质,二肽等含量高于未辐照组烟叶,而亮氨酸、L-丝氨酸和脯氨酸等氨基酸含量低于未辐照烟叶。KEGG富集差异显著的代谢通路是黄酮和黄酮醇生物合成通路与花生四烯酸代谢通路。(3)发酵28 d后,两组烟叶的生物碱、还原糖、总糖、淀粉和蛋白质含量均显著降低,辐照组烟叶发酵前后各指标的降幅小于未辐照烟叶。辐照组烟叶发酵28 d后中性香气成分总量显著低于未辐照烟叶,而棕色化反应产物总量显著增加,烟叶劲头、杂气、刺激性更大。【结论】对发酵前烟叶进行10 kGy^(60)Co-γ射线辐照可有效杀灭烟叶细菌,发酵28 d后大分子物质降解转化低于未辐照烟叶,感官质量增加幅度减小,但相比于发酵前仍有一定程度的改善。 展开更多
关键词 雪茄烟叶 ^(60)co-γ射线 发酵 微生物 代谢组学 烟叶质量
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Aluminum-air battery with cotton substrate:Controlling the discharge capacity by electrolyte pre-deposition 被引量:2
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作者 Wending Pan Yifei Wang +1 位作者 Holly Y.H.Kwok Dennis Y.C.Leung 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期757-766,共10页
Conventional Al-air battery has many disadvantages for miniwatt applications,such as the complex water management,bulky electrolyte storage and potential leakage hazard.Moreover,the self-corrosion of Al anode continue... Conventional Al-air battery has many disadvantages for miniwatt applications,such as the complex water management,bulky electrolyte storage and potential leakage hazard.Moreover,the self-corrosion of Al anode continues even when the electrolyte flow is stopped,leading to great Al waste.To tackle these issues,an innovative cotton-based aluminum-air battery is developed in this study.Instead of flowing alkaline solution,cotton substrate pre-deposited with solid alkaline is used,together with a small water reservoir to continuously wet the cotton and dissolve the alkaline in-situ.In this manner,the battery can be mechanically recharged by replacing the cotton substrate and refilling the water reservoir,while the thick aluminum anode can be reused for tens of times until complete consumption.The cotton substrate shows excellent ability for the storage and transportation of alkaline electrolyte,leading to a high peak power density of 73 mW cm^(-2) and a high specific energy of 930 mW h g^(-1).Moreover,the battery discharge capacity is found to be linear to the loading of pre-deposited alkaline,so that it can be precisely controlled according to the mission profile to avoid Al waste.Finally,a two-cell battery pack with common water reservoir is developed,which can provide a voltage of 2.7 V and a power output of 223.8 mW.With further scaling-up and stacking,this cotton-based Al-air battery system with low cost and high energy density is very promising for recharging miniwatt electronics in the outdoor environment. 展开更多
关键词 Al-air battery Cotton-based Electrolyte pre-deposition Capacity control Miniwatt electronics
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Crude oil cracking in deep reservoirs:A review of the controlling factors and estimation methods 被引量:2
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作者 Yu Qi Chun-Fang Cai +2 位作者 Peng Sun Dao-Wei Wang Hong-Jian Zhu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期1978-1997,共20页
The natural cracking of crude oils in deep reservoirs has gained great interest due to continuously increasing depth of petroleum exploration and exploitation.Complex oil compositions and surroundings as well as compl... The natural cracking of crude oils in deep reservoirs has gained great interest due to continuously increasing depth of petroleum exploration and exploitation.Complex oil compositions and surroundings as well as complicated geological evolutions make oil cracking in nature much more complex than industrial pyrolysis.So far,numerous studies,focused on this topic,have made considerable progress although there still exist some drawbacks.However,a comprehensive review on crude oil cracking is yet to be conducted.This article systematically reviews the controlling factors of oil cracking from six aspects,namely,oil compositions,temperature and time,pressure,water,minerals and solid organic matter.We compare previous experimental and modelling results and present new field cases.In the following,we evaluate the prevailing estimation methods for the extent of oil cracking,and elucidate other factors that may interfere with the application of these estimation methods.This review will be helpful for further investigations of crude oil cracking and provides a guide for estimation of the cracking extent of crude oils. 展开更多
关键词 Oil cracking Deep reservoir controlling factor Gas to oil ratio Diamondoid
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