检索结果-南通市图书馆

Effects of Temperature, Acetate and Nitrate on Methane Generation from Petroleum Hydrocarbons

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2014年第4期16卷 24-31页

作者： Liu Chunshuang Zhao Dongfeng zhang yunbo College of Chemical Engineering China University of PetroleumQingdao

In this study, the effects of temperature, acetate and nitrate on methane gas production from biodegradation of petroleum hydrocarbons were investigated. The results indicated that methane gas production at 35 ℃ was higher than that obtained at 55 ℃. The acetate addition significant enhanced the methane production at 35 ℃, however, at 55 ℃ the nitrate addition could largely promote the methane production. The microbial community structures were revealed by PCR-DGGE. The Actinobacteria, Clostridia, Clostridiales, Syntrophus, Pseudomonas, and Proteobacteria-like bacteria and Methanocellales, Methanosaeta, Methanomicrobiales, Methanolinea, Thermoprotei-like archaea had been enriched at 35 ℃ in the acetate addition test. The Thermoprotei, Proteobacterium, Thermodesulfovibrio-like bacteria and Methanocellales-like archaea had been enriched at 55 ℃ in the nitrate addition test. The results may shed light on the bio-utilization of marginal oil reservoirs for enhancing energy recovery.

关键词： petroleum hydrocarbons nitrate methane microbial community

Collisional dynamics of symmetric two-dimensional quantum droplets

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2022年第6期17卷 203-209页

作者： Yanming Hu Yifan Fei Xiao-Long Chen yunbo zhang Institute of Theoretical Physics and State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China Department of Physics and Key Laboratory of Optical Field Manipulation of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou 310018China

The collisional dynamics of two symmetric droplets with equal intraspecies scattering lengths and particle number density for each component is studied by solving the corresponding extended Gross–Pitaevskii equation in two dimensions by including a logarithmic correction term in the usual contact *** find the merging droplet after collision experiences a quadrupole oscillation in its shape and the oscillation period is found to be independent of the incidental momentum for small *** increasing collision momentum the colliding droplets may separate into two,or even more,and finally into small pieces of *** these dynamical phases we manage to present boundaries determined by the remnant particle number in the central area and the damped oscillation of the quadrupole mode.A stability peak for the existence of droplets emerges at the critical particle number Nc≃48 for the quasi-Gaussian and flat-top shapes of the droplets.

关键词： ultracold atoms quantum droplets collisions

Necessity of orthogonal basis vectors for the two-anyon problem in a one-dimensional lattice

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第12期76卷 62-74页

作者： Cuicui Zheng Jiahui Xie Ming zhang Yajiang Chen yunbo zhang Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation Department of Physics Zhejiang Sci-Tech University

Few-body physics for anyons has been intensively studied within the anyon-Hubbard model,including the quantum walk and Bloch oscillations of two-anyon states. Recently, theoretical and experimental simulations of two-anyon states in a one-dimensional lattice have been carried out by expanding the wavefunction in terms of non-orthogonal basis vectors, resulting in nonphysical degrees of freedom. In the present work, we deduce finite difference equations for the two-anyon state in a one-dimensional lattice by solving the Schr?dinger equation with orthogonal and complete basis vectors. Such an orthogonal scheme gives all the orthogonal physical eigenstates, while the conventional(non-orthogonal) method produces many nonphysical redundant eigensolutions whose components violate the anyonic commutation *** dynamical property of the two-anyon states in a sufficiently large lattice is investigated and compared in both the orthogonal and conventional schemes. For initial states with two anyons at the same site or two(next-)neighboring sites, we observe the same dynamical behavior in both schemes, including the revival probability, probability density function and two-body correlation. For other initial states, the conventional scheme produces erroneous states that no longer obey the anyonic relations. The period of Bloch oscillations in the pseudo-fermionic limit has been found to be twice that in the bosonic limit, while these oscillations disappear at other statistical parameters. Our findings are vital for quantum simulations of few-body anyonic physics in lattice models.

关键词： anyon-Hubbard model Bloch oscillations quantum simulation quantum walk two-anyon states

Characteristics of Milankovitch Cycles in the Mid-Permian Liangshan and Qixia Formations of the Sichuan Basin——Examples from Well-Long17 and Well-Wujia1

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2012年第5期86卷 1045-1059页

作者： zhang yunbo JIA Chengzao ZHAO Zongju JIANG Zaixing XU Jie China University of Geosciences Beijing 100083China Chinese Petroleum Society Beijing 100724China

The Liangshan and Qixia formations in the Sichuan Basin of central China were formed in the earlier middle Permian. Based on outcrop observation of the Changjianggou section at Shangsi, Guangyuan region and 3 rd -order sequence division in typical drillings, one-dimensional spectrum analysis has been used to choose the better curve between the natural gamma ray spectrometry log（ln （Th/K）） in Well-Long17 and the gamma ray log（GR） in Well-Wujia1, respectively, for identifying Milankovitch cycles in Sequence PSQ1 which comprises the Liangshan and Qixia formations, and then to identify the variation in the Milankovitch cycle sequences. On this basis, the system tract and 4 th -order sequence interfaces in Sequence PSQ1 were found via two-dimensional spectral analysis and digital filtering. Finally, a high-frequency sequence division program was established. Among these cycles, long eccentricity （413.0 ka） and short eccentricity （123.0 ka） are the most unambiguous, and they are separately the major control factors in forming 4 th -order （parasequence sets） and 5 th -order （parasequences） sequences, with the average thicknesses corresponding to the main cycles being 11.47 m and 3.32 m in Well-Long17, and 14.21 m and 3.79 m in Well-Wujia1, respectively. In other words, the deposition rate in the beach subfacies is faster than that of the inner ramp facies. The ln（Th/K） curve is more sensitive than the GR as the index of relatively ancient water depth in carbonate deposition. One-dimensional spectrum analysis of ln（Th/K） curve could distinguish the Milankovitch cycle sequences that arose from the Precession cycle （20.90 ka）, with a much higher credibility. Sequence PSQ1 in Well-Long17 contains 10 4 th -order sequences, and the growth span of Sequence PSQ1 consisting of the Liangshan and Qixia formations is about 4.13 Ma. The single deposition thickness of the long eccentricity cycle sequence has the characteristics of thinning and then thickening in the two-dimensional spec

关键词： sedimentary characteristics Thorium/Potassium (Th/K) ratio logs Milankovitch cycle Permian Sichuan basin

Online preparation of high-quality BN coatings with atomic diffusion based on carbon-free water-soluble precursor

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第3期13卷 272-281页

作者： Yiang Du Bing Wang yunbo zhang Quzhi Song Fuwen Wang Cheng Han Xiaoshan zhang Yingde Wang Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Efficient and environmentally friendly production of high-quality continuous fiber coatings using current preparation methods is highly challenging due to issues such as scale and batch processing restrictions,low deposition rate,high energy consumption,and utilization of multiple environmentally hazardous *** address these challenges,we propose a stable and efficient wet chemical deposition coating method for high-throughput online continuous preparation of boron nitride(BN)coatings on ceramic fibers under an ambient *** process involves surface modification,in-situ wet chemical deposition,and heat treatment,and all seamlessly connecting with the ceramic fiber preparation process through continuous *** groups were introduced via surface modification enhancing wettability of the fiber surface with impregnating *** in-situ reaction and atom migration improve uniformity and binding of the *** a result,outstanding impregnation and adhesion properties are achieved.A comprehensive analysis to evaluate the impact of the BN coatings was conducted,which demonstrates that the BN-coated fibers exhibit a remarkable 36%increase in tensile strength,a 133%increase in fracture toughness,and enhanced temperature resistance of up to 1600℃.It provides a secure and efficient platform for cost-effective production of functional and high-quality coatings through targeted surface modification and rapid stretching impregnation.

关键词： polymer-derived ceramics SiC fibers wet chemical deposition atomic diffusion boron nitride(BN)coatings

Type division and controlling factor analysis of 3rd-order sequences in marine carbonate rocks

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2014年第2期5卷 289-298页

作者： yunbo zhang Zongju Zhao Genhou Wang Zaixing Jiang Mingjian Wang Min Zheng Shiben zhang China University of Geosciences (Beijing) Chinese Petroleum Society Qingdao Institute of Marine Geology Research Institute of Petroleum Exploration and Development

Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehensive analysis of carbon and oxygen isotope trends, paleobathymetry and spectral-frequency of representative well logs, 3rd-order sequences can be divided into 3 types：（a） global sea level （GSL） sequence mainly controlled by GSL change;（b） tectonic sequence mainly controlled by regional tectonic activity;and （c） composite sequence jointly controlled by GSL change and regional tectonic activity. This study aims to identify the controlling factors of 3rd-order sequences and to illustrate a new method for classification of 3rd-order sequences of the middle Permian strata in the Sichuan Basin, China. The middle Permian strata in the Sichuan Basin consist of 3 basin-contrastive 3rd-order sequences, i.e., PSQ1, PSQ2 and PSQ3. Of these, PSQ1 is a GSL sequence while PSQ2 and PSQ3 are composite sequences. The results suggest that the depositional environment was stable during the deposition of PSQ1, but was activated by tectonic activity during the deposition of the middle Permian Maokou Formation.

关键词： Carbon isotope 3rd-Order sequence Milankovitch cycles Middle Permian strata Sichuan Basin

Optimization for Microbial Degradation of Dibenzothiophene by Pseudomonas sp. LKY-5 Using Response Surface Methodology

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2014年第1期16卷 19-26页

作者： Li Lin Zhao Chaocheng Liu Qiyou zhang yunbo Liu Chunshuang Xue Jianliang College of Chemical Engineering China University of Petroleum Qingdao

In this research, the degradation of dibenzothiophene(DBT) was investigated by using Pseudomonas sp. LKY-5 isolated from oil contaminated soil. The response surface methodology(RSM) based on the Box-Behnken design(BBD) was applied for evaluating the interactive effects of four independent variables including substrate concentration, temperature, pH and agitation rate on the DBT removal response. A total of 29 experiments for four factors at three levels were conducted in present study. A second-order regression model was then developed, and the analysis of variance(ANOVA) illustrated that the proposed quadratic model could be utilized to navigate the design space. The value of determination coefficient(R2=0.953 4) indicated a satisfactory agreement between the quadratic model and the experimental data. It was found that DBT removal was more significantly affected(P<0.000 1) by substrate concentration compared with other three parameters. An 100% degradation of DBT could be obtained by Pseudomonas sp. LKY-5 at a substrate concentration of 100 mg/L.

关键词： degradation dibenzothiophene Pseudomonas sp. response surface methodology Box–Behnken design

Study on Isolation, Identification of A Petroleum Hydrocarbon Degrading Bacterium Bacillus fusiformis sp. and Influence of Environmental Factors on Degradation Efficiency

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2011年第4期13卷 74-82页

作者： Zhao Dongfeng Wu Weilin zhang yunbo Liu Qiyou Yang Haibin Zhao Chaocheng Department of Environmental Engineering China University of Petroleum Qingdao 266555 Petroleam Engineering Technology Research Institute Jiangsu Oil Exploration Corporation Yangzhou 225009

A hydrocarbon degrading bacterium KL2-13 was isolated from ten sites of oil contaminated soil in the Karamay oilfield. It was identified as the Bacillusfusiformis sp. bacterium based on its morphological and physiological characteristics and the 16S rDNA sequence analysis. The factors influencing the hydrocarbon degradation by the bacterium KL2-13 were determined. The test results have showed that the hydrocarbon degrading bacterium KL2-13 requires an optimum pH range of 6-8, and the optimum inoculation quantity is 3%. The low-concentration metal ions Fe^2＋, Mg^2＋ and Ca^2＋can improve the degradation ability of the bacteria KL2-13. A too low concentration of Tween-80 does not show obvious promotion to the degrading bacterium KL2-13, and an excessively high concentration can decrease the degradation ability of the bacterium, the best dosage of which is 2%. The hydrocarbon degrading rate reached 59.07%4-0.37% under the optimum culture conditions.

关键词： hydrocarbon degrading bacterium Bacillusfusiformis sp. environmental factor surfactant hydrocarbon degradation rate

Vertical Graphenes Grown on a Flexible Graphite Paper as an All-Carbon Current Collector towards Stable Li Deposition

在线全文

学校读者我要写书评

暂无评论

Research 2020年第1期2020卷 1222-1232页

作者： Zhijia Huang Debin Kong yunbo zhang Yaqian Deng Guangmin Zhou Chen zhang Feiyu Kang Wei Lv Quan-Hong Yang Shenzhen Geim Graphene Center(SGC) Tsinghua-Berkeley Shenzhen Institute(TBSI)Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Shenzhen Key Laboratory for Graphene-based Materials Engineering Laboratory for Functionalized Carbon MaterialsTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Nanoyang Group State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Lithium(Li)metal has been regarded as one of the most promising anode materials to meet the urgent requirements for the next-generation high-energy density ***,the practical use of lithium metal anode is hindered by the uncontrolled growth of Li dendrites,resulting in poor cycling stability and severe safety ***,vertical graphene(VG)film grown on graphite paper(GP)as an all-carbon current collector was utilized to regulate the uniform Li nucleation and suppress the growth of *** high surface area VG grown on GP not only reduces the local current density to the uniform electric field but also allows fast ion transport to homogenize the ion gradients,thus regulating the Li deposition to suppress the dendrite *** Li deposition can be further guided with the lithiation reaction between graphite paper and Li metal,which helps to increase lithiophilicity and reduce the Li nucleation barrier as well as the *** a result,the VG film-based anode demonstrates a stable cycling performance at a current density higher than 5mAcm^(-2)in half cells and a small hysteresis of 50mV at 1mAcm^(-2)in symmetric *** work provides an efficient strategy for the rational design of highly stable Li metal anodes.

关键词： cycling Vertical hysteresis