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现代化工 2017年第1期37卷 176-179页

作者：谷邵伟蒋洪张世坚唐雯周茜王昱珩西南石油大学石油与天然气工程学院四川成都610500 西南油气田重庆气矿重庆400021

通过比选各种液化流程的能耗及适应性优选出适合页岩气试采期单井液化流程;利用HYSYS模拟分析了单循环混合制冷液化工艺,比较了不同压力工况下液化流程的适应性及能耗变化。模拟计算可对国内试采期天然气回收利用提供参考。

关键词：页岩气液化试采期天然气回收单循环液化工艺

亚热带杉木林土壤有机碳及其活性组分对氮磷添加的响应

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应用生态学报 2017年第2期28卷 449-455页

作者：张秀兰王方超方向民何平张宇飞陈伏生王辉民江西农业大学林学院江西特色林木资源培育与利用201.协同创新中心南昌330045 中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室千烟洲生态试验站北京100101

通过野外氮、磷添加,分析N_0(0 kg N·hm^(-2)·a^(-1.)、N_1.50 kg N·hm^(-2)·a^(-1.)、N_2(1.0 kg N·hm^(-2)·a^(-1.)、P(50 kg P·hm^(-2)·a^(-1.)、N_1.和N_2P等6种处理3年后对亚热带杉木人工林土壤有机碳(SOC)、颗粒有机碳(POC)和水溶性有机碳(WSOC)的影响.结果表明:氮、磷添加对0~20 cm土层SOC含量无显著影响.磷添加显著降低0~5 cm土层POC含量,与无磷处理相比,加磷处理POC含量降低26.1..WSOC含量对氮、磷添加的响应主要表现在0~5 cm土层,低水平氮添加和磷添加显著提高WSOC含量.在0~5 cm土层,氮添加对POC/SOC值无显著影响,而与无磷添加相比,POC/SOC值在磷添加处理下显著降低1..9%.在5~1.和1.~20 cm土层,氮、磷添加处理对POC/SOC值无显著影响.在亚热带地区,森林土壤碳稳定性主要受磷含量的调控,短期磷添加易导致表层土壤活性有机碳分解,增加土壤碳稳定性.

关键词：氮沉降磷添加颗粒有机碳水溶性有机碳

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替格瑞洛的晶体结构研究

中国现代应用药学 2017年第6期34卷 868-870页

作者：霍立茹许麒麟赵卿张慧南京济群医药科技股份有限公司南京211100 中国药科大学南京211100

目的建立单晶X-射线衍射法来确证替格瑞洛的绝对构型。方法应用SHELXTL-97晶体软件程序包通过直接法和最小二乘法来确定替格瑞洛晶体结构和每一个手性碳原子的绝对构型。结果替格瑞洛晶体属于正交晶系,F222空间群,a=22.1.2(4)?,b=34.1.5... 详细信息

目的建立单晶X-射线衍射法来确证替格瑞洛的绝对构型。方法应用SHELXTL-97晶体软件程序包通过直接法和最小二乘法来确定替格瑞洛晶体结构和每一个手性碳原子的绝对构型。结果替格瑞洛晶体属于正交晶系,F222空间群,a=22.1.2(4)?,b=34.1.5(9)?,c=1..31.(3)?,V=1. 848(4)?3,R1.0.081.1.w R2=0.1.7 8,Flack参数为-0.1.(1.)。结论替格瑞洛分子中存在6个手性C中心,分别为C1.C2,C3,C5,C1.和C1.,其构型分别为S,S,R,S,R,S。

关键词：替格瑞洛晶体培养晶体结构解析

Diatomic Pd catalyst with conjugated backbone for synergistic electrochemical CO_(2)reduction

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Nano Research 2024年第6期17卷 4850-4855页

作者： Wenxuan zhang Mengran zhang Hongjuan Wang Wen zhang Min zhang MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading,adjustable active centres,and electronic valence ***,the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory ***,we designed and synthesized a bimetallic palladium complex(BPB-Pd_(2))with conjugated *** supported BPB-Pd_(2)was applied to electrochemical CO_(2)reduction reaction(CO_(2)RR)for the first *** as-obtained BPB-Pd_(2)gives an exceptional Faradaic efficiency of CO(FECO)of 94.4%at−0.80 V *** hydrogen electrode(RHE),which is significantly superior to monoatomic palladium catalyst(BPB-Pd1..The density functional theory(DFT)calculations revealed that the essential reason for the outstanding activity of BPB-Pd_(2)toward CO_(2)RR was that the electronic effect between diatomic palladium reduces the free energy change for CO_(2)RR ***,BPB-Pd_(2)exhibits moderate free energy change to form COOH*intermediate,which was beneficial for the generation of CO in CO_(2)RR.

关键词： synthesis electrocatalysis CO_(2)reduction bimetallic palladium complex synergistic catalysis

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1.t% N-GQD, denoted as 0.1. G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1. G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1., respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1. the H2 production activity of 0.1.G-TPCN under visible light is enhanced by 1..4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1. G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1. G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1370页

作者： Lele REN Wei zhang Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell,in cases of 1.2 inter-well internal resonance and primary *** transverse foundation excitation is applied to the fixed end of the structure,and the other end is in a free *** first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control *** four-dimensional averaged equations are derived in both polar and rectangular coordinate *** from the obtained frequency-amplitude and force-amplitude response curves,a detailed analysis is conducted to examine the impacts of excitation amplitude,damping coefficient,and tuning parameter on the nonlinear internal resonance characteristics of the *** nonlinear softening characteristic is exhibited in the upper stable-state,while the lower stable-state demonstrates the softening and linearity *** simulation is carried out using the fourth-order Runge-Kutta method,and a series of nonlinear response curves are *** the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： bistable composite laminated cantilever shell inter-well internal resonance primary resonance chaotic dynamic snap-through complex nonlinear vibration

Improving lipid production by Rhodotorula glutinis for renewable fuel production based on machine learning

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 23-35页

作者： Lihe zhang Changwei zhang Xi Zhao Changliu He Xu zhang National Energy R&D Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China Collage of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Bioprocess Beijing University of Chemical TechnologyBeijing 10029China

Microbial lipid fermentation encompasses intricate complex cell growth processes and heavily relies on expert experience for optimal *** modeling of the fermentation process assists researchers in making intelligent decisions,employing logical reasoning and strategic planning to optimize lipid *** this study,the effects of medium components and concen-trations on lipid fermentation were investigated,*** then,leveraging the collated data,a variety of machine learning algorithms were used to model and optimize the lipid fermentation *** models,based on artificial neural networks and support vector machines,achieved R?values all higher than 0.93,ensuring accurate predictions of the fermentation *** linear regression was used to evaluate the respective target parameter,which were affected by the medium components of lipid ***,single and multi-objective optimiza-tion were conducted for lipid fermentation using the genetic *** results demonstrated the maximum biomass of 50.3 g·L^(-1. and maximum lipid concentration of 1..1.g:L^(-1. with the error between the experimental and predicted values less than 5%.The results of the multi-objective optimization reveal the synergistic and competitive relationship between biomass,lipid concentration,and conversion rate,which lay a basis for in-depth optimization and amplification.

关键词： microbial lipid machine learning artificial neural network support vector machine genetic algorithm

Non-isothermal kinetics and characteristics of calcium carbide nitridation reaction with calcium-based additives

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 49-61页

作者： Zhihan zhang Mengxiao Yu Xiaoyu zhang Jinli zhang You Han School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The nitridation reaction of calcium carbide and N_(2) at high temperatures is the key step in the production of ***,the challenges faced by this process,such as high energy consumption and poor product quality,are mainly attributed to the lack of profound understanding of the *** study aimed to improve this process by investigating the non-isothermal kinetics and reaction characteristics of calcium carbide nitridation reaction at different heating rates(1.,1.,20,and 30℃·min^(-1.)using thermogravimetric *** kinetic equation for the nitridation reaction of additive-free calcium carbide sample was obtained by combining model-free methods and model-fitting *** effect of different calcium-based additives(CaCl_(2) and CaF_(2))on the reaction was also *** results showed that the calcium-based additives significantly reduced reaction temperature and activation energy E_(a) by about 40% with CaF_(2) and by 55%-60% with CaCl_(2).The reaction model f(α)was also changed from contracting volume(R3)to 3-D diffusion models with D3 for CaCl_(2) and D4 for CaF_(2).This study provides valuable information on the mechanism and kinetics of calcium carbide nitridation reaction and new insights into the improvement of the lime-nitrogen process using calcium-based additives.

关键词： lime-nitrogen calcium carbide calciumbased additive thermogravimetric analysis nonisothermal kinetics

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祛斑止痒膏成型工艺实验研究

时珍国医国药 2004年第4期15卷 219-220页

作者：潘明云张会宗孔黎冰李成森辽宁省中医研究院辽宁电力中心医院辽宁省中医研究院辽宁沈阳 1.0034 辽宁沈阳 1.001.

目的:建立祛斑止痒膏成型工艺条件。方法:通过软膏性状和药物稳定性的考察,确立投料次序,并通过软膏止痒效果对比,确定透皮吸收促进剂种类。结果:实验研究的基质敷料处方,按药材与基质敷料1.:7比例,加3％月桂氰卓酮(Azone)作为透皮吸收... 详细信息

目的:建立祛斑止痒膏成型工艺条件。方法:通过软膏性状和药物稳定性的考察,确立投料次序,并通过软膏止痒效果对比,确定透皮吸收促进剂种类。结果:实验研究的基质敷料处方,按药材与基质敷料1.:7比例,加3％月桂氰卓酮(Azone)作为透皮吸收促进剂混合成型,稳定性好,膏体性状及疗效均较佳。结论:实验确定的成型工艺条件切实可行,适于工业生产。

关键词：祛斑止痒膏成型工艺透皮吸收促进剂

Periodic Variation Studies of the Two Short Period W UMa-type Eclipsing Binaries: LX Lyn and V0853 Aur

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Research in Astronomy and Astrophysics 2024年第1期24卷 273-284页

作者： Xu zhang Bin zhang School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China

In this paper,new light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 201. version of the Wilson-Devinney(W-D) *** order to explain their asymmetric LCs,cool starspots on the components were *** is suggested that their fill-out degrees are f=1..0%(LX Lyn) and f=26.3%(V0853 Aur).At the same time,we found that LX Lyn is a W-type eclipsing binary(EB) with an orbital inclination of i=84°.88 and a mass ratio of q=2.31.V0853 Aur is also a W-type CEB with a mass ratio of q=2.77 and an orbital inclination of i= 79°.*** on all available times of light minimum,their orbital period changes are studied by using the O-C *** O-C diagram of LX Lyn reveals a cyclic oscillation with a period of about 1..84 yr and an amplitude of 0.001. days,which can be explained by the light-travel time effect(LTTE) due to the presence of a third body with a minimum mass of0.06M_⊙.For V0853 Aur,it is discovered that the O-C diagram of the system also shows a cyclic oscillation with a period of 9.64 yr and an amplitude of 0.03365 *** cyclic oscillation of V0853 Aur can be attributed to the LTTE by means of a third body with a mass no less than 3.77M_⊙.The third body may play an important role in the formation and evolution of these systems.

关键词： stars:activity (stars:)binaries(including multiple):close (stars:)binaries:eclipsing (stars:)brown dwarfs stars:evolution stars:formation