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Interface optimization and defects suppression via Na F introduction enable efficient flexible Sb_(2)Se_(3) thin-film solar cells
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作者 Mingdong Chen Muhammad Ishaq +7 位作者 Donglou Ren Hongli Ma Zhenghua Su Ping Fan David Le Coq Xianghua Zhang Guangxing Liang Shuo Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期165-175,I0006,共12页
Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible devices.However,the power conversion efficiency(PCE) of f... Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible devices.However,the power conversion efficiency(PCE) of flexible Sb_(2)Se_(3) photovoltaic devices is temporarily limited by the complicated intrinsic defects and the undesirable contact interfaces.Herein,a high-quality Sb_(2)Se_(3) absorber layer with large crystal grains and benign [hkl] growth orientation can be first prepared on a Mo foil substrate.Then NaF intermediate layer is introduced between Mo and Sb_(2)Se_(3),which can further optimize the growth of Sb_(2)Se_(3)thin film.Moreover,positive Na ion diffusion enables it to dramatically lower barrier height at the back contact interface and passivate harmful defects at both bulk and heterojunction.As a result,the champion substrate structured Mo-foil/Mo/NaF/Sb_(2)Se_(3)/CdS/ITO/Ag flexible thin-film solar cell delivers an obviously higher efficiency of 8.03% and a record open-circuit voltage(V_(OC)) of 0.492 V.This flexible Sb_(2)Se_(3) device also exhibits excellent stability and flexibility to stand large bending radius and multiple bending times,as well as superior weak light photo-response with derived efficiency of 12.60%.This work presents an effective strategy to enhance the flexible Sb_(2)Se_(3) device performance and expand its potential photovoltaic applications. 展开更多
关键词 Sb_(2)Se_(3) Flexible solar cells NaF intermediate layer Interface optimization Defects suppression
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Cookie Baking Process Optimization and Quality Analysis Based on Food 3D Printing
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作者 Liu Chenghai Li Jingyi +2 位作者 Wu Chunsheng Zhao Xinglong Zheng Xianzhe 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期61-73,共13页
In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the in... In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the influences of baking process parameters, such as baking time, surface heating temperature and bottom heating temperature, on the quality of the cookie were studied to optimize the baking process parameters. The results showed that the baking process parameters had obvious effects on the texture, color, deformation, moisture content, and temperature of the cookie. All of the roasting surface heating temperature, bottom heating temperature and baking time had positive influences on the hardness, crunchiness, crispiness, and the total color difference(ΔE) of the cookie. When the heating temperatures of the surfac and bottom increased, the diameter and thickness deformation rate of the cookie increased. However,with the extension of baking time, the diameter and thickness deformation rate of the cookie first increased and then decreased. With the surface heating temperature of 180 ℃, the bottom heating temperature of 150 ℃, and baking time of 15 min, the cookie was crisp and moderate with moderate deformation and uniform color. There was no burnt phenomenon with the desired quality. Research results provided a theoretical basis for cookie manufactory based on food 3D printing technology. 展开更多
关键词 food 3D printing baking process COOKIE quality analysis optimization of process parameter
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达比加群酯-d_(3)的合成 被引量:1
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作者 王昌 梁林辉 +2 位作者 姚永秀 梁大伟 董金华 《化学试剂》 CAS 2024年第1期105-110,共6页
研究抗凝血药物达比加群酯-d_(3)的合成工艺。以4-氯-3-硝基苯甲酸甲酯为起始原料,氘代甲胺盐酸盐为氘代试剂,经氘代甲基化、取代、还原、缩合、环合、水解、亲核等反应得到关键氘化中间体3-{[(2-{[(4-氰基苯基)氨基]甲基}-1-(甲基-d_(... 研究抗凝血药物达比加群酯-d_(3)的合成工艺。以4-氯-3-硝基苯甲酸甲酯为起始原料,氘代甲胺盐酸盐为氘代试剂,经氘代甲基化、取代、还原、缩合、环合、水解、亲核等反应得到关键氘化中间体3-{[(2-{[(4-氰基苯基)氨基]甲基}-1-(甲基-d_(3))苯并咪唑-5-基)氧亚基](吡啶-2-基)氨基}丙酸乙酯,而后再经氨解和亲核反应,成功制备稳定的达比加群酯-d_(3),8步反应总产率为6.4%,目标化合物结构经NMR和MS确认,同位素丰度达99.7%。该合成方法原料简单易得、操作简便、重现性好,可用于达比加群酯-d_(3)的合成。 展开更多
关键词 抗凝血药物 达比加群酯-d_(3) 合成工艺 优化 同位素标记
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Scheme for the implementation of 1 → 3 optimal phase-covariant quantum cloning in ion-trap systems 被引量:2
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作者 杨榕灿 李洪才 +2 位作者 林秀 黄志平 谢鸿 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期967-970,共4页
This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant i... This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies. 展开更多
关键词 resonant interaction 1→3 optimal phase-covariant quantum cloning trapped ions
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Novel learning framework for optimal multi-object video trajectory tracking
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作者 Siyuan CHEN Xiaowu HU +2 位作者 Wenying JIANG Wen ZHOU Xintao DING 《Virtual Reality & Intelligent Hardware》 EI 2023年第5期422-438,共17页
Background With the rapid development of Web3D, virtual reality, and digital twins, virtual trajectories and decision data considerably rely on the analysis and understanding of real video data, particularly in emerge... Background With the rapid development of Web3D, virtual reality, and digital twins, virtual trajectories and decision data considerably rely on the analysis and understanding of real video data, particularly in emergency evacuation scenarios. Correctly and effectively evacuating crowds in virtual emergency scenarios are becoming increasingly urgent. One good solution is to extract pedestrian trajectories from videos of emergency situations using a multi-target tracking algorithm and use them to define evacuation procedures. Methods To implement this solution, a trajectory extraction and optimization framework based on multi-target tracking is developed in this study. First, a multi-target tracking algorithm is used to extract and preprocess the trajectory data of the crowd in a video. Then, the trajectory is optimized by combining the trajectory point extraction algorithm and Savitzky-Golay smoothing filtering method. Finally, related experiments are conducted, and the results show that the proposed approach can effectively and accurately extract the trajectories of multiple target objects in real time. Results In addition, the proposed approach retains the real characteristics of the trajectories as much as possible while improving the trajectory smoothing index, which can provide data support for the analysis of pedestrian trajectory data and formulation of personnel evacuation schemes in emergency scenarios. Conclusions Further comparisons with methods used in related studies confirm the feasibility and superiority of the proposed framework. 展开更多
关键词 WEB3D Virtual evacuation Multi-object tracking Trajectory extraction Trajectory optimization
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Autonomous UAV 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains
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作者 Andrey V.Savkin Satish C.Verma Wei Ni 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期154-160,共7页
This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors ha... This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data buffers.The ground sensor model takes into account sensor data buffer and battery limitations.An asymptotically globally optimal method of joint UAV 3D trajectory optimization and data transmission schedule is developed.The developed method maximizes the amount of data transmitted to the UAV without losses and too long delays and minimizes the propulsion energy of the UAV.The developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic programming.Computer simulations demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 Unmanned aerial system UAS Unmanned aerial vehicle UAV Wireless sensor networks UAS-Assisted data collection 3D trajectory optimization Data transmission scheduling
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A Non-Singleton Type-3 Fuzzy Modeling: Optimized by Square-Root Cubature Kalman Filter
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作者 Aoqi Xu Khalid A.Alattas +3 位作者 Nasreen Kausar Ardashir Mohammadzadeh Ebru Ozbilge Tonguc Cagin 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期17-32,共16页
In many problems,to analyze the process/metabolism behavior,a mod-el of the system is identified.The main gap is the weakness of current methods vs.noisy environments.The primary objective of this study is to present a... In many problems,to analyze the process/metabolism behavior,a mod-el of the system is identified.The main gap is the weakness of current methods vs.noisy environments.The primary objective of this study is to present a more robust method against uncertainties.This paper proposes a new deep learning scheme for modeling and identification applications.The suggested approach is based on non-singleton type-3 fuzzy logic systems(NT3-FLSs)that can support measurement errors and high-level uncertainties.Besides the rule optimization,the antecedent parameters and the level of secondary memberships are also adjusted by the suggested square root cubature Kalmanfilter(SCKF).In the learn-ing algorithm,the presented NT3-FLSs are deeply learned,and their nonlinear structure is preserved.The designed scheme is applied for modeling carbon cap-ture and sequestration problem using real-world data sets.Through various ana-lyses and comparisons,the better efficiency of the proposed fuzzy modeling scheme is verified.The main advantages of the suggested approach include better resistance against uncertainties,deep learning,and good convergence. 展开更多
关键词 MODELING computational intelligence fuzzy logic systems MODELING identification deep learning type-3 fuzzy systems optimization
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Thermodynamic Analysis and Optimization of the C3/MRC Liquefaction Process
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作者 Guisheng Wang 《Energy Engineering》 EI 2023年第6期1503-1514,共12页
In the natural gas liquefaction process,the mixed refrigerant natural gas liquefaction process is widely used in LNG liquefaction plants because of its advantages of low energy consumption.This paper focuses on the in... In the natural gas liquefaction process,the mixed refrigerant natural gas liquefaction process is widely used in LNG liquefaction plants because of its advantages of low energy consumption.This paper focuses on the influences of important parameters in the C3/MRC liquefaction process,that is,the comparison between propane precooling temperature and the number of moles of methane in mixed refrigerant,power consumption and loss.In addition,the total process was optimized with the optimizer and manual adjustment in HYSYS software to minimize the total power consumption.The results show that with increasing propane precooling temperature,the propane flow rate is almost unchanged,while the mixed refrigerant flow rate decreases significantly,and the loss of the heat exchanger increases significantly.The power consumption of the propane precooling cycle and hybrid refrigeration cycle increases with increasing methane content in the refrigerant,so the power consumption of the whole process increases accordingly.The effect of the methane content in the mixed refrigerant on the process evaluation index is more significant than that of the propane precooling temperature. 展开更多
关键词 C3/MRC process propane precooling temperature methane content optimIZATION
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固定化脂肪酶ANL-MARE催化酸解合成1-油酸-2-棕榈酸-3-亚油酸甘油三酯
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作者 康梦 何家强 +7 位作者 冯孔龙 黄早成 李一峰 苗建银 符姜燕 朱泽榕 刘果 曹庸 《现代食品科技》 CAS 北大核心 2024年第2期109-119,共11页
1-油酸-2-棕榈酸-3-亚油酸甘油三酯(OPL)是人乳中主要的脂质组成,为满足婴幼儿配方食品母乳化需求,该试验探究了新型固定化脂肪酶ANL-MARE催化制备OPL的方法。试验成功制备和表征了固定化酶ANLMARE,并以ANL-MARE为生物催化剂,建立了一... 1-油酸-2-棕榈酸-3-亚油酸甘油三酯(OPL)是人乳中主要的脂质组成,为满足婴幼儿配方食品母乳化需求,该试验探究了新型固定化脂肪酶ANL-MARE催化制备OPL的方法。试验成功制备和表征了固定化酶ANLMARE,并以ANL-MARE为生物催化剂,建立了一种用三棕榈酸甘油三酯(PPP)、油酸(OA)和亚油酸(LA)高效酶催化制备富含OPL结构脂的方法。经单因素和响应面试验优化,获得OPL最优合成工艺为:PPP与总脂肪酸的摩尔比1:14.27,OA与LA摩尔比为1:0.76,脂肪酶添加量12.70%,反应温度50℃,反应4 h,此条件下产物中OPL相对含量为47.93%,2位棕榈酸(sn-2 PA)占总棕榈酸(PA)的质量分数(sn-2 PA相对含量)为71.69%。此外,固定化酶ANL-MARE与商业脂肪酶相比,表现出较好的催化合成OPL的活性。综上所述,固定化酶ANL-MARE具有催化制备OPL结构脂的重大潜力,为人乳脂替代脂的高效制备提供了新策略和理论基础。 展开更多
关键词 1-油酸-2-棕榈酸-3-亚油酸甘油三酯 酶促酸解法 固定化脂肪酶 ANL-MARE 工艺优化
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A Survey on Type-3 Fuzzy Logic Systems and Their Control Applications
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作者 Oscar Castillo Fevrier Valdez +1 位作者 Patricia Melin Weiping Ding 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1744-1756,共13页
In this paper,we offer a review of type-3 fuzzy logic systems and their applications in control.The main objective of this work is to observe and analyze in detail the applications in the control area using type-3 fuz... In this paper,we offer a review of type-3 fuzzy logic systems and their applications in control.The main objective of this work is to observe and analyze in detail the applications in the control area using type-3 fuzzy logic systems.In this case,we review their most important applications in control and other related topics with type-3 fuzzy systems.Intelligent algorithms have been receiving increasing attention in control and for this reason a review in this area is important.This paper reviews the main applications that make use of Intelligent Computing methods.Specifically,type-3 fuzzy logic systems.The aim of this research is to be able to appreciate,in detail,the applications in control systems and to point out the scientific trends in the use of Intelligent Computing techniques.This is done with the construction and visualization of bibliometric networks,developed with VosViewer Software,which it is a free Java-based program,mainly intended to be used for analyzing and visualizing bibliometric networks.With this tool,we can create maps of publications,authors,or journals based on a co-citation network or construct maps of keywords,countries based on a co-occurrence networks,research groups,etc. 展开更多
关键词 Applications control systems optimization REVIEW type-3 fuzzy logic.
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磁性Ce-La-MOFs@Fe_(3)O_(4)的除氟性能
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作者 宋江燕 翟涛 +5 位作者 温倩 周融融 杨为森 简绍菊 潘文斌 胡家朋 《材料导报》 EI CAS CSCD 北大核心 2024年第4期38-44,共7页
通过水热法制备了Ce-La-MOFs@Fe_(3)O_(4)复合材料,研究了Ce-La-MOFs@Fe_(3)O_(4)对水溶液中F^(-)的吸附性能,并通过响应曲面法优化了吸附条件。实验结果表明:在pH=3.6、实验温度为40℃、初始氟离子浓度为17.4 mg/L的条件下,Ce-La-MOFs@... 通过水热法制备了Ce-La-MOFs@Fe_(3)O_(4)复合材料,研究了Ce-La-MOFs@Fe_(3)O_(4)对水溶液中F^(-)的吸附性能,并通过响应曲面法优化了吸附条件。实验结果表明:在pH=3.6、实验温度为40℃、初始氟离子浓度为17.4 mg/L的条件下,Ce-La-MOFs@Fe_(3)O_(4)的吸附效果最佳,F^(-)去除率可达94.5%。除氟特性实验数据更适合用Langmuir模型进行描述,拟合得到最大吸附容量(q_(max))为147.23 mg/g,热力学参数ΔG^(o)、ΔH^(o)和ΔS^(o)表明该吸附反应是一个自发吸热的熵增过程。动力学研究表明Ce-La-MOFs@Fe_(3)O_(4)对F^(-)的吸附符合准二级反应动力学过程。对复合材料的形貌和结构进行了表征分析,并结合吸附热力学和动力学研究探讨了吸附机理,该吸附过程主要是离子交换和静电吸附共同作用。共存离子实验、循环再生实验结果显示,Ce-La-MOFs@Fe_(3)O_(4)对F^(-)具有较好的选择性,该复合材料的再生性能较好,回收率可达96%,两次循环后对F^(-)的去除率仍达81.74%。 展开更多
关键词 磁性Ce-La-MOFs@Fe_(3)O_(4) 除氟 吸附 响应曲面优化
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湖南省“3+5”城市群农业功能权衡-协同特征及优化研究
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作者 刘悦 安悦 +1 位作者 谭雪兰 任辉 《湖南师范大学自然科学学报》 CAS 北大核心 2024年第2期99-108,共10页
农业各功能之间保持着相互增进的协同关系或此消彼长的权衡关系。本研究以湖南省“3+5”城市群地区的县(区)为研究单元,从生产功能、生态功能和生活功能3个维度构建农业功能评价指标体系,利用熵值法、Spearman秩相关系数法和双变量局部... 农业各功能之间保持着相互增进的协同关系或此消彼长的权衡关系。本研究以湖南省“3+5”城市群地区的县(区)为研究单元,从生产功能、生态功能和生活功能3个维度构建农业功能评价指标体系,利用熵值法、Spearman秩相关系数法和双变量局部空间自相关模型等对农业功能演变及协同-权衡关系进行测度。结果表明:(1)农业生产功能整体呈增强态势;农业生活功能呈先上升后下降的趋势;农业生态功能往城市群外围扩散。(2)在协同与权衡关系上,农业生产功能和其他两项功能空间分布变动较大,具有较强的不稳定性,生产功能和其他两项功能的协同与权衡关系在空间分布上较为稳定。(3)功能分区上可划分为5种组合类型:生产功能优势区、生活功能优势区、生态功能优势区、多功能并重区和农业功能弱势区。 展开更多
关键词 农业功能 权衡与协同 聚类优化 湖南省“3+5”城市群
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Application of Topology Optimization Technology based on Inspire and 3D Printing in Lightweight Design of Quadrotor UAV
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作者 SONG Xiaobo LI Xijin MAO Qiuying 《International Journal of Plant Engineering and Management》 2023年第1期45-58,共14页
This paper takes the fuselage bracket of the quadrotor UAV as the object,combined with the characteristics of less constraints in the 3D printing process,achieves the optimal structure of the UAV body structure design... This paper takes the fuselage bracket of the quadrotor UAV as the object,combined with the characteristics of less constraints in the 3D printing process,achieves the optimal structure of the UAV body structure design form,using the inspire topology optimization analysis,with the optimization goal of maximizing the overall stiffness and the optimized structure was checked for strength and verified by 3D printing prototype.The results show that under the premise of meeting the design strength and stiffness requirements,the mass is reduced by 53.29%compared with the original design.The research shows that the application of topology optimization and 3D printing technology to the structural design of UAVs will achieve significant weight reduction effects,providing a feasible way to realize lightweight,complex and integrated design and manufacturing of components. 展开更多
关键词 INSPIRE topology optimization 3D printing UAV lightweight design
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重组大肠杆菌发酵条件优化提高D-阿洛酮糖3-差向异构酶活性的研究
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作者 刘微微 常楚婷 +4 位作者 冯敬杰 张家赫 李飞胜 丁文涛 王昌禄 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期253-259,共7页
功能性稀有糖D-阿洛酮糖主要由基因工程菌株表达D-阿洛酮糖3-差向异构酶(D-allulose 3-epimerase,DAE)催化果糖生产。该研究以表达DAE的重组大肠杆菌为研究对象,利用单因素试验对发酵培养基的碳源、氮源、金属离子等成分进行优化,获得... 功能性稀有糖D-阿洛酮糖主要由基因工程菌株表达D-阿洛酮糖3-差向异构酶(D-allulose 3-epimerase,DAE)催化果糖生产。该研究以表达DAE的重组大肠杆菌为研究对象,利用单因素试验对发酵培养基的碳源、氮源、金属离子等成分进行优化,获得了最佳的培养基组合:蔗糖10 g/L、大豆蛋白胨15 g/L、(NH4)2SO_(4)3 g/L、KH2PO_(4)3 g/L、MgSO_(4)0.5 g/L、MnSO_(4)0.025 mmol/L。在此基础上,利用单因素试验对培养条件进行研究,确定了最佳发酵诱导时间(10 h)、接种量(3%,摇瓶)、装液量(30%)以及异丙基-β-D-硫代半乳糖苷(isopropyl-beta-D-thiogalactopyranoside,IPTG)添加浓度(1 mmol/L),使OD_(600)增加了1.46倍,酶活提高了2.57倍。在此基础上,利用5 L发酵罐进行放大发酵实验,确定了最佳诱导时间。在最佳条件下,经过18 h的诱导发酵,菌体OD_(600)最高值达51.8,干重达到21.5 g/L,酶活达到103.8 U/mL。当细胞添加量为0.014 g DCW/L时,以500 g/L D-果糖为底物,pH为7,50℃,1 h转化率达28.76%,D-阿洛酮糖最高生成量可达149.74 g/L。该研究对D-阿洛酮糖3-差向异构酶的发酵生产具有参考价值。 展开更多
关键词 D-阿洛酮糖-3-差向异构酶 重组大肠杆菌 高密度发酵 发酵优化 重组蛋白
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The First Global Map of Atmospheric Ammonia(NH_(3)) as Observed by the HIRAS/FY-3D Satellite
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作者 Minqiang ZHOU Zhili DENG +6 位作者 Charles ROBERT Xingying ZHANG Lu ZHANG Yapeng WANG Chengli QI Pucai WANG Martine De MAZIÈRE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期379-390,共12页
Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentra... Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentration based on the absorption lines of NH_(3) in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH_(3)column from the Hyperspectral Infrared Atmospheric Sounder(HIRAS) onboard the Chinese Feng Yun(FY)-3D satellite and present the first atmospheric NH_(3) column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH_(3) hotspots around the world, e.g., India, West Africa, and East China, where large NH_(3) emissions exist. The HIRAS NH_(3) columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer(IASI)measurements, and we find that the two instruments observe a consistent NH_(3) global distribution, with correlation coefficient(R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH_(3) retrieval are discussed. 展开更多
关键词 AMMONIA HIRAS/FY-3D satellite thermal-infrared observation remote sensing optimal estimation method
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Optimized air-ground data fusion method for mine slope modeling
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作者 LIU Dan HUANG Man +4 位作者 TAO Zhigang HONG Chenjie WU Yuewei FAN En YANG Fei 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2130-2139,共10页
Refined 3D modeling of mine slopes is pivotal for precise prediction of geological hazards.Aiming at the inadequacy of existing single modeling methods in comprehensively representing the overall and localized charact... Refined 3D modeling of mine slopes is pivotal for precise prediction of geological hazards.Aiming at the inadequacy of existing single modeling methods in comprehensively representing the overall and localized characteristics of mining slopes,this study introduces a new method that fuses model data from Unmanned aerial vehicles(UAV)tilt photogrammetry and 3D laser scanning through a data alignment algorithm based on control points.First,the mini batch K-Medoids algorithm is utilized to cluster the point cloud data from ground 3D laser scanning.Then,the elbow rule is applied to determine the optimal cluster number(K0),and the feature points are extracted.Next,the nearest neighbor point algorithm is employed to match the feature points obtained from UAV tilt photogrammetry,and the internal point coordinates are adjusted through the distanceweighted average to construct a 3D model.Finally,by integrating an engineering case study,the K0 value is determined to be 8,with a matching accuracy between the two model datasets ranging from 0.0669 to 1.0373 mm.Therefore,compared with the modeling method utilizing K-medoids clustering algorithm,the new modeling method significantly enhances the computational efficiency,the accuracy of selecting the optimal number of feature points in 3D laser scanning,and the precision of the 3D model derived from UAV tilt photogrammetry.This method provides a research foundation for constructing mine slope model. 展开更多
关键词 Air-ground data fusion method Mini batch K-Medoids algorithm Ebow rule optimal cluster number 3D laser scanning UAV tilt photogrammetry
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Linking a Simulated Annealing Based Optimization Model with PHT3D Simulation Model for Chemically Reactive Transport Processes to Optimally Characterize Unknown Contaminant Sources in a Former Mine Site in Australia
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作者 Bithin Datta Claire Petit +2 位作者 Marine Palliser Hamed K. Esfahani Om Prakash 《Journal of Water Resource and Protection》 2017年第5期432-454,共23页
Historical mining activities often lead to continuing wide spread contaminants in both groundwater and surface water in previously operational mine site areas. The contamination may continue for many years after closi... Historical mining activities often lead to continuing wide spread contaminants in both groundwater and surface water in previously operational mine site areas. The contamination may continue for many years after closing down the mining activities. The essential first step for sustainable management of groundwater and development of remediation strategies is the unknown contaminant source characterization. In a mining site, there are multiple species of contaminants involving complex geochemical processes. It is difficult to identify the potential sources and pathways incorporating the chemically reactive multiple species of contaminants making the source characterization process more challenging. To address this issue, a reactive transport simulation model PHT3D is linked to a Simulated Annealing based the optimum decision model. The numerical simulation model PHT3D is utilized for numerically simulating the reactive transport process involving multiple species in the former mine site area. The simulation results from the calibrated PHT3D model are illustrated, with and without incorporating the chemical reactions. These comparisons show the utility of using a reactive, geochemical transport process’ simulation model. Performance evaluation of the linked simulation optimization methodology is evaluated for a contamination scenario in a former mine site in Queensland, Australia. These performance evaluation results illustrate the applicability of linked simulation optimization model to identify the source characteristics while using PHT3D as a numerical reactive chemical species’ transport simulation model for the hydro-geochemically complex aquifer study area. 展开更多
关键词 Groundwater CONTAMINATION Source Characterization PHT3D Linked SIMULATION optimization Methodology Chemically Reactive Transport SIMULATION MINE SITE CONTAMINATION Simulated Annealing
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地生弯颈霉C41-3产低温脂肪酶发酵条件优化
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作者 孙蕊 苏丹 +1 位作者 张文浩 吕国忠 《安徽农业科学》 CAS 2024年第2期1-4,共4页
[目的]优化地生弯颈霉C41-3产低温脂肪酶发酵条件,为扩大低温脂肪酶的应用提供理论依据。[方法]使用棕榈酸对硝基苯酯(p-NPP)比色法测定脂肪酶的活性。[结果]最佳发酵培养基为胰蛋白胨40 g/L、α-乳糖20 g/L、MnSO_(4)·H_(2)O 1 g/... [目的]优化地生弯颈霉C41-3产低温脂肪酶发酵条件,为扩大低温脂肪酶的应用提供理论依据。[方法]使用棕榈酸对硝基苯酯(p-NPP)比色法测定脂肪酶的活性。[结果]最佳发酵培养基为胰蛋白胨40 g/L、α-乳糖20 g/L、MnSO_(4)·H_(2)O 1 g/L、NH_(4)NO_(3)1 g/L、乳化芥花油20 mL;最佳发酵条件为pH 5、发酵温度15℃、培养时间4 d。优化后,地生弯颈霉C41-3的脂肪酶活性从199.40 U/mL增加至5700.72 U/mL,脂肪酶活性增加了约27.6倍。[结论]该新型脂肪酶具有潜在的工业应用价值。 展开更多
关键词 低温脂肪酶 地生弯颈霉C41-3 发酵条件优化
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三孩政策下0—3岁婴幼儿托育服务存在的问题与对策
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作者 王婉纯 《黑龙江教师发展学院学报》 2024年第6期146-152,共7页
2021年三孩政策在全国范围内正式实施,使得托育服务成为民生刚性需求。随着托育服务事业的迅速发展,其面临的一系列困境值得关注。从托育服务的四大主体政府、社会、教师和家庭四方面分析当前0—3岁婴幼儿托育服务存在的问题。在此基础... 2021年三孩政策在全国范围内正式实施,使得托育服务成为民生刚性需求。随着托育服务事业的迅速发展,其面临的一系列困境值得关注。从托育服务的四大主体政府、社会、教师和家庭四方面分析当前0—3岁婴幼儿托育服务存在的问题。在此基础上,提出相应的优化对策,即完善政策体系与托育制度,持续加大政府扶持力度,重点发展普惠性托育服务,提高托育服务质量,加强托育人员队伍建设,发展特色早教课程,创新社区托育模式等,以期促进0—3岁婴幼儿健康成长。 展开更多
关键词 三孩政策 0—3岁婴幼儿 托育服务 问题 优化对策
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郑州地铁3号线二期建筑方案研究与设计实践
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作者 王冠龙 《山西建筑》 2024年第9期26-29,共4页
从郑州地铁3号线二期四座车站建筑设计方案展开论述,对方案变化过程、设计重难点等进行了分析,并就建设过程中发生的主要问题及解决方案进行了归纳总结,提出可供后续其他地铁线路建设推广的主要经验与建议。
关键词 郑州地铁3号线二期 地铁车站 建筑设计 换乘节点优化 侧式站 车站规模控制
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