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Multi-Stage Hydrocarbon Accumulation and Formation Pressure Evolution in Sinian Dengying FormationCambrian Longwangmiao Formation, Gaoshiti-Moxi Structure, Sichuan Basin

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Journal of Earth Science 2016年第5期27卷 835-845页

作者： Juan Wu Shugen Liu Guozhi Wang Yihua zhao wei Sun Jinming song Yanhong Tian State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences Chuanzhong Division of Southwest Oil & Gasfield Company Petro China

Sichuan Basin is a typical superimposed basin, which experienced multi-phase tectonic movements, meanwhile Sinian–Cambrian underwent complex hydrocarbon accumulation processes, causing exploration difficulties in the past 60 years. Based on the microscopic evidence of fluid inclusions, combined with basin-modelling, this paper determines stages and time of hydrocarbon accumulation, reconstructs evolution of formation pressure and dynamic processes of hydrocarbon accumulation in Sinian Dengying Formation-Cambrian Longwangmiao Formation of Gaoshiti-Moxi structure. Three stages of inclusions are detected, including a stage of yellow-yellowgreen fluorescent oil inclusions, a stage of blue fluorescent oil-gas inclusions and a stage of non-fluorescent gas inclusions, reflecting the study area has experienced a series of complex hydrocarbon accumulation processes, such as formation of paleo-oil reservoirs, cracking of crude oil, formation of paleo-gas reservoirs and adjustment to present gas reservoirs, which occurred during 219–188, 192–146 and 168–0 Ma respectively. During the period of crude oil cracking, Dengying Formation-Longwangmiao Formation showed weak overpressure to overpressure characteristics, then after adjustment of paleo-gas reservoirs to present gas reservoirs, the pressure in Dengying Formation changed into overpressure but finally reduced to normal pressure system. However, due to excellent preservation conditions, the overpressure strength in Longwangmiao Formation only slightly decreased and was still kept to this day.

关键词： Sichuan Basin Gaoshiti-Moxi structure Sinian-Cambrian hydrocarbon accumulation,formation pressure fluid inclusion.

Field emission properties of amorphous GaN ultrathin films fabricated by pulsed laser deposition

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Science in China(Series F) 2009年第10期52卷 1947-1952页

作者： WANG FengYing WANG RuZhi zhao wei song XueMei WANG Bo YAN Hui Laboratory of Thin Film College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

Amorphous gallium nitride （a-GaN） films with thicknesses of 5 and 300 nm are deposited on n-Si （100） substrates by pulsed laser deposition （PLD）, and their field emission （FE） properties are studied. It shows that compared with thicker （300 nm） a-GaN film, better FE performance is obtained on ultrathin （5 nm） a-GaN film with a threshold field of 0.78 V/μm, which is the lowest value ever reported. Furthermore, the current density reaches 42 mA/cm2 when the applied field is 3.72 V/μm. These experimental results unambiguously confirm Binh＇s theoretical analysis （Binh et al. Phys Rev Lett, 2000, 85（4）： 864-867） that the FE performance would be prominently enhanced with the coating of an ultra-thin wide band-gap semiconductor film.

关键词： field emission amorphous gallium nitride (a-GaN) pulsed laser deposition (PLD) work function

Effect of vibrating electrode on temperature profiles,fluid flow,and pool shape in ESR system based on a comprehensive coupled model

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China Foundry 2015年第4期12卷 285-292页

作者： Fang Wang Yan-chun Lou Rui Chen zhao-wei song Bao-kuan Li School of Materials and Metallurgy Northeastern University Shenyang Research Institute of Foundry

The vibrating electrode method was proposed in the electro-slag remelting （ESR） process in this paper, and the effect of vibrating electrode on the solidification structure of ingot was studied. A transient three- dimensional （3D） coupled mathematical model was established to simulate the electromagnetic phenomenon, fluid flow as well as pool shape in the ESIR process with the vibrating electrode. The finite element volume method is developed to solve the electromagnetic field using ANSYS mechanical APDL software. Moreover, the electromagnetic force and Joule heating are interpolated as the source term of the momentum and energy equations. The multi-physical fields have been investigated and compared between the traditional electrode and the vibrating electrode in the ESR process. The results show that the drop process of metal droplets with the traditional electrode is scattered randomly. However, the drop process of metal droplets with the vibrating electrode is periodic. The highest temperature of slag layer with the vibrating electrode is higher than that with the traditional electrode, which can increase the melting rate due to the enhanced heat transfer in the vicinity of the electrode tip. The results also show that when the amplitude and frequency of the vibrating electrode increase, the cycle of drop process of metal droplets decreases significantly.

关键词： electro-slag remelting process vibrating electrode magneto-hydrodynamic numerical simulation

Energy transfer in organic multilayer quantum well structure and its application to OLEDs

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Optoelectronics Letters 2007年第2期3卷 99-102页

作者： zhao De-wei song Shu-fang zhao Su-ling XU Zheng Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China

We fabricate a series of samples and OLEDs with organic multilayer quantum well structure, which consist of alternate PBD and Alqy Both PBD and Alq3 are electron-transporting materials, and PBD is used as potential barrier layer, while Alq3 is used as potential well layer and emitting layer. Compared with double-layer structure, the luminescent characteristics of organic samples and diodes with quantum well structure are investigated and the quantum well structure helps the energy transfer between well layer and barrier layer. The quantum well structure makes carriers disperse in the different well layers and then increases the number of excitons to enhance the efficiency of the recombination.

关键词：有机多层量子阱结构能量传递 OLED 应用

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第1期68卷 209-216页

作者： Yixin Yang Wanlei zhao Ruoxuan Zheng Hongqiang Li wei Chen Yu-Fei song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Quzhou Institute for Innovation in Resource Chemical Engineering

The purification and size sieving of nanoparticles （NPs） represents a significant scientific ***,the r GO-polyoxometalates (POMs=PMo12,Mo132and Mo368) membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of r GO to PMo12was 1:30,the resultant r GO-PMo12membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots（CQDs） separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo12（1.0 nm）,{Mo132}（2.9 nm） to{Mo368}（3.8 nm）,the resultant r GO-PMo12,r GO-Mo132and r GO-Mo368exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional （2D） membranes for highly efficient size-selective separation.

关键词： reduced graphene oxide polyoxometalates membranes gradient separation nanoparticles

Elimination of cracks in stainless steel casings via 3D printed sand molds with an internal topology structure

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China Foundry 2024年第4期21卷 319-326页

作者： Jun-hang Xu Bao-zhi Li zhao-wei song Yun-bao Gao Jing-ming Li Yu Wang Qiu-lin Wen Heng Cao Zeng-rui Wang National Key Laboratory of Advanced Casting Technologies Shenyang 110022China Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China

The important supporting component in a gas turbine is the casing,which has the characteristics of large size,complex structure,and thin *** the context of existing 3DP sand casting processes,casting crack defects are prone to *** leads to an increase in the scrap rate of casings,causing significant resource ***,the presence of cracks poses a significant safety hazard after the casings are put into *** generation of different types of crack defects in stainless steel casings is closely related to casting stress and the high-temperature concession of the sand ***,the types and causes of cracks in stainless steel casing products,based on their structural characteristics,were systematically *** sand molds with different internal topology designs were printed using the 3DP technology to investigate the impact of sand mold structures on high-temperature *** optimal sand mold structure was used to cast casings,and the crack suppression effect was verified by analyzing its eddy current testing *** experimental results indicate that the skeleton structure has an excellent effect on suppressing cracks in the *** research holds important theoretical and engineering significance in improving the quality of casing castings and reducing production costs.

关键词： gas turbine casing crack defects 3D printed sand mold topological structure high-temperature concession

The PhoR/PhoP two-component system regulates fengycin production in Bacillus subtilis NCD-2 under low-phosphate conditions

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Journal of Integrative Agriculture 2018年第1期17卷 149-157页

作者： GUO Qing-gang DONG Li-hong WANG Pei-pei LI She-zeng zhao wei-song LU Xiu-yun ZHANG Xiao-yun MA Ping Institute of Plant Protection Hebei Academy of Agriculture and Forestry Sciences/Integrated Pest Management Center of Hebei Province/Key Laboratory of IPM on Crops in Northern Region of North ChinaMinistry of Agriculture

Bacillus subtilis strain NCD-2 is an excellent biocontrol agent for plant soil-borne diseases, and the lipopeptide fengycin is one of the active antifungal compounds in strain NCD-2. The regulator PhoP and its sensor kinase PhoR compose a two-component system in B. subtilis. In this study, the phoR- and phoP-knockout mutants were constructed by in-frame deletion and the role of PhoR/PhoP on the production of fengycin was determined. Inactivation of phoR or phoP in B. subtilis decreased its inhibition ability against Botrytis cinerea growth in vitro compared to the strain NCD-2 wild type. The lipopeptides were extracted from strain NCD-2 wild type and its mutant strains by hydrochloric acid precipitate, and the lipopeptides from phoR-null mutant orphoP-null mutant almost lost the inhibition ability against B. cinerea growth compared to the lipopeptides from strain NCD-2 wild type. Fast protein liquid chromatography （FPLC） analysis of the lipopeptides showed that inactivation of phoR or phoP genes reduced the production of fengycin by strain NCD-2. The fengycin production abilities were compared for bacteria under low-phosphate medium （LPM） and high-phosphate medium （HPM）, respectively. Results indicated that the regulation of fengycin production by the PhoR/PhoP two-component system occurred in LPM but not in HPM. Reverse transcriptionaI-PCR confirmed that the fengycin synthetase gene fenC was positively regulated by phoP when cultured in LPM. All of these characteristics could be partially restored by complementation of intact phoR or phoP gene in the mutant. These data indicated that the PhoR/PhoP two-component system greatly regulated fengycin production and antifungal ability in B. subtilis NCD-2 mainly under low-phosphate conditions.

关键词： Bacillus subtilis two-component system Iipopeptides transcriptional factor PhoR/PhoP

Studies on the Inclusion Complex Reaction and Fluorescent Analytical Application of β- cyclodextrin with Hymecromone

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Wuhan University Journal of Natural Sciences 1999年第4期4卷 473-476页

作者： LUO zhao fu, song wei, PAN Zu ting  College of Chemistry and Environmental Science, Wuhan University, Wuhan 430072, China College of Chemistry and Environmental Science Wuhan University Wuhan China

The inclusion complex reaction condition and the mechanism of β cyclodextrin with hymecromone have been studied by fluorescent spectrum. The fluorescent intensity and the stability of the system can be qreatly increased in qiven condition, and the formation constant of the inclusion complex reaction has been determined too. The system can be applied to the determination of trace amounts of hymecromone, the maximum fluorescent intensity is obtained with excitation and emission wavelength at 362 nm and 452 nm, respectively. The linear range for hymecromone is 8.0×10 -9 mol·L -1 to 1.0×10 -5 mol·L -1 . The detection limit is 1.8×10 -9 mol·L -1 . A simple, rapid and highly sensitive fluorimetric method is proposed for the determination of hymecromone. The results obtained are in agreement with those given by an official method.

关键词： Fluorescent spectra hymecromone β cyclodextrin inclusion complex

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun Xu song Gu Fulong Chen Zhe zhao Peng Liu Daoben Hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams