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Model-based in-situ measurement of pakchoi leaf area

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International Journal of Agricultural and Biological Engineering 2015年第4期8卷 35-42页

作者： gong liang Chen Ran Zhao Yuanshen Liu Chengliang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Leaf area measurement is of great significance in plant growth process *** poses challenges to perform an unattended in-situ measurement,arising from quantifying the 3-dimensional pakchoi leaf *** non-destructive measurement techniques,which usually take its projection on the horizon plane of the leaf area,inevitably cause considerable measurement *** order to improve the measurement precision for leaf area,the exemplar pakchoi leaf was modeled as a complete or a piecewise spatial plane to approximate the actual leaf surface,and a machine-vision based ad hoc measuring platform was developed to conduct the in-situ ***,the leaf image was captured by a stereo vision system and segmented via a semi-automatic process to obtain its projective area and spatial inclination ***,pakchoi leaves were modeled as spatial surfaces regarding to their projected ***,leaf areas were calculated according to the established planar spatial model,acquired inclination angles and projective *** experimental comparison among the lattice-based monotype method,projection method,and the model-based method,whose results are denoted as MA,PA,and EA respectively,showed that the proposed framework could simultaneously meet the accuracy and non-destructive measurement *** constructed platform also provided a cost-effective semi-automatic measurement approach for continuously in-situ monitoring of pakchoi growth during its whole cultivation *** is further suggested from the experimental results that the proposed methodology can offer a generic measurement solution to various kinds of plant physiological and ecological studies in future researches.

关键词： leaf area in-situ measurement non-destructive measurement stereo vision image processing

Thermal Performance and Mechanics Characteristic for Double Layer Microchannel Heat Sink

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Journal of Thermal Science 2019年第2期28卷 271-282页

作者： XU Yupeng gong liang LI Yongtong BAI Zhang XU Minghai Department of Energy & Power Engineering China University of Petroleum (East China)

Double layer micro-channel heat sink(DLMCHS) has been widely used in various electronic devices; however, the existence of the nonuniform thermal strain distribution in actual operation has adverse effect on the overall stability. In this paper, two optimized designs of DLMCHS with cutting baffles on top and bottom layers are presented based on the traditional DLMCHS. The heat transfer and thermal stress performance are numerically analyzed and compared with the traditional DLMCHS. The results indicate that cutting baffles of micro-channels remarkably improves heat transfer and thermal stress performance. The optimized design with cutting baffles on the bottom layer decreases thermal strain but deteriorates heat transfer performance. The model with cutting baffles on the top layer has better combined thermal strain and heat transfer performance, which reduces thermal strain by about 1.5 times and enhances heat transfer by about 26.5%. For the design with cutting baffles on the top board, adding metal foam in the inlet collector can decrease the total minimum thermal strain by 51.4% and maximum temperature by 1.4 K, and increase the Nusselt number by 15%. These results indicate that DLMCHS with cutting baffles on the top layer has great potential for thermal managements on electronic devices with high power density.

关键词： double layer micro-channel heat sink thermal strain thermal performance optimized design

Phase Prediction of Supercritical Carbon Dioxide and its Application in Fracturing Oil Wellbores

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Journal of Thermal Science 2019年第3期28卷 484-493页

作者： gong liang CHEN Shichao ZUO Jiaqiang BAI Bin BAI Zhang College of Pipeline and Civil Engineering China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Petroleum Engineering Technology Research Institute Sinopec Shengli oil field

In recent oil and gas exploration, the most reservoirs are low permeability with abundant reserves. Conventional mining of low permeability reservoir is commonly utilizing the hydraulic fracturing technology, whereas, it encounters various technical issues, such as clay expansion and water lock damage. Using the fluid of supercritical carbon dioxide(S-CO_2) to exploit the low permeability oil and gas reservoirs is attracting more attention. The implementation of S-CO_2, without liquid phase, can help avoid the aforementioned problems. Nevertheless, the phase change of CO_2 during fracturing is complicate, and it is difficult to accurately predict the CO_2 phase transition. In this work, first, the physical properties of S-CO_2 were analyzed by the Span-Wagner model and Vesovic model. Next, S-CO_2 was applied to a typical oilfield, and an unsteady coupling model of heat transfer and pressure drop was developed. Then the staggered grid method and iteration procedures were used for numerical solutions, and the temperature and pressure distributions of wellbores were investigated. The results indicate that the temperature control of a wellbore is the key to the phase prediction of S-CO_2; CO_2 within the single-diameter pipeline below 2300 m can maintain the supercritical state, while CO_2 within the stepped pipeline can maintain the supercritical state at the depth of 2280 m. Moreover, compared with the single-diameter pipeline, the bottom pressure of the stepped pipeline is lower and the bottom temperature is higher. By analyzing the flow and heat transfer of S-CO_2 in the wellbores, the phase state of S-CO_2 was well predicted, which is helpful to improve the exploring performance of low permeability oil and gas reservoirs.

关键词： supercritical carbon dioxide unsteady-state heat transfer phase prediction wellbore

Nanocarrier based on the assembly of protein and antisense oligonucleotide to combat multidrug resistance in tumor cells

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Science China Chemistry 2017年第10期60卷 1318-1323页

作者： Xuan Yu liang gong Jing Zhang Zilong Zhao Xiaobing Zhang Weihong Tan Molecular Science and Biomedicine Laboratory State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering College of Life Sciences and Aptamer Engineering Center of Hunan Province Hunan University Changsha 410082 China

Chemotherapy-induced multi-drug resistance(MDR) in tumors poses a huge challenge for clinical treatment of tumors. The downregulation of the multi-drug resistance relative protein, represented by P-glycoprotein(P-gp), can reverse MDR of cancer cells. In this study, we developed doxorubicin-loading nanocarrier based on the assembly of protein and antisense oligonucleotide(ASO) to combat MDR of cancer cells. The data demonstrate that the nanocarrier can efficiently deliver ASO to cytoplasm and downregulate the P-glycoprotein expression, subsequently improving the therapeutic effects of Dox in doxorubicin-resistant MCF-7/ADR cancer cells. The preparation is simple and effective, providing a powerful tool for gene delivery. Therefore, our nanocarrier shows high promise in cancer treatment.

关键词： multi-drug resistance P-glycoprotein antisense oligonucleotide nanocarrier

Circularly polarized phosphorescence and photon transport of micro/nanocrystals of ruthenium and iridium complexes with chiral anions

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Science China Chemistry 2023年第10期66卷 2892-2902页

作者： Zhong-Qiu Li Zhong-liang gong Tongling liang Stefan Bernhard Yu-Wu Zhong Jiannian Yao Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of PhotochemistryCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Chemistry Carnegie Mellon UniversityPittsburghPennsylvania 15213USA

Materials with efficient circularly polarized phosphorescences(CPPs) are of potential use in advanced data encryption and anticounterfeiting, bioimaging, optoelectronic devices and so forth. Herein, a simple method is presented for the preparations of CPP-active micro/nanocrystals with large luminescence dissymmetry factors(glum), high phosphorescence quantum efficiencies(Φ_(P)) and tunable emission colors. Diastereomeric Ir^(Ⅲ) and Ru^(Ⅱ) complexes with chiral(±)-camphorsulfonate counter-anions are readily synthesized and assembled into crystalline microrods, microplates or nanofibers with ordered morphologies. The chirality information of chiral counter-anions is efficiently transferred to the metal components to afford CPPs with cyan, green,yellow, or red emission colors and Φ_(P)in the range of 5%–85%. The number of chiral anions is found to play a role in influencing the CPP magnitudes of these crystals. The dicationic Ru^(Ⅱ) and tricationic Ir^(Ⅲ) complexes show glumvalues in the 10^(-2)order, which are much larger with respect to those of monocationic Ir^(Ⅲ) complexes. Single crystal X-ray analysis is performed to obtain information on the chirality transfer of these materials. In addition, circularly polarized photonic signal waveguiding is demonstrated using the microcrystals of an Ir^(Ⅲ)complex. This work demonstrates an appealing strategy of constructing chiral micro/nano-architectures for potential applications in chiral nanophotonics.

关键词： circularly polarized luminescence transition metal complexes chirality transfer micro/nanocrystals photon transport

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Dynamic subsidence basins in coal mines based on rock mass rheological theory

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Mining Science and Technology 2011年第3期21卷 333-335页

作者： Yang Yu gong Zhiqiang liang Bing School of Civil Engineering and Transportation Liaoning Technical University Fuxin 123000 China

In order to investigate the surface deformation caused by coal mining and to reduce environmental damage, more accurate information of dynamic subsidence basins, caused by coal mining, is needed. Based on theological theory, we discuss surface deformation mechanism of dynamic subsidence on the assumption that both the roof and the coal seam are visco-elastic media, put forward the idea that the principle of surface deformation is similar to that of roofs, except for their parameters. Therefore, a surface deforma- tion equation can be obtained, given the equation of the roof deformation *** using a HIM rhe- ological model. In the end, we apply the equation of surface deformation as a practical subsidence prediction in a coal mine. Given the theologic properties of a rock mass, the results of our research of a dynamic subsidence basin can predict the development of surface deformation as a function of time, which is more important than the ultimate subsidence itself. The results indicate that using rheological theory to calculate the deformation of a dynamic subsidence basin is suitable and provides some reference for surface deformation of dynamic subsidence basins.

关键词： Coal mining subsidenceDynamic basinRheological theorie sHiM theological model

Preparation of nitric humic acid by catalytic oxidation from Guizhou coal with catalysts

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International Journal of Mining Science and Technology 2012年第1期22卷 75-78页

作者： Yang Zhiyuan gong liang Ran Pan School of Chemistry and Chemical Engineering Xi'an University of Sdence and TechnologyXi'an 710054.China

Nitric humic acid was prepared by catalytic oxidation between nitric acid and Guizhou coal, with added catalysts. We investigated catalytic oxidation processes and the factors that affect the reactions. The effects of different catalysts, including NiSO4 support on active carbon （AC-NiS04）, NiS04 support on sil- icon dioxide （SiO2-NiSO4）, composites of SO42-1Fe203, Zr-iron and vanadium-iron composite were stud- ied. As well, we investigated nitric humic acid yields and the chemical structure of products by element analysis, FT-IR and E4/E6 （an absorbance ratio at wavelengths of 465 and 665 nm of humic acid alkaline extraction solutions）. The results show that the catalytic oxidation reaction with added catalysts can increase humic acid yields by 18.7%, 16.36% 12.94%, 5.61% and 8.59%, respectively. The highest yield of humic acid, i.e., 36.0%, was obtained with AC-NiSO4 as the catalyst. The amounts of C and H decreased with the amount of nitrogen. The increase in the E4/E6 ratio in catalytic oxidation of （Guizhou） coal shows that small molecular weights and high yields of nitric humic acid can be obtained by catalytic oxidation reactions.

关键词： Guizhou coal Catalytic oxidation Humic acid Catalysts

Non-interactive identity-based threshold signature scheme without random oracles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第6期9卷 727-736页

作者： Xun SUN Jian-hua LI Shu-tang YANG gong-liang CHEN Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Information Security Engineering Shanghai Jiao Tong University Shanghai 200240 China

A (t, n) threshold signature scheme distributes the secret key and hence the signing ability to n players in a way that any set of t+1 or more honest players can collaborate to sign, while any set of t players cannot. In this paper we propose an iden- tity-based threshold signature (IBTHS) scheme from bilinear pairings. The signing phase of our scheme is non-interactive, meaning that the signing players do not need to talk to each other. We prove our scheme secure (i.e., unforgeable and robust) in the standard model (i.e., without random oracles). No earlier proposed IBTHS scheme achieved even one of the features of being non-interactive (in the signing phase) and secure in the standard model.

关键词： Bilinear pairings Identity-based threshold signature (IBTHS) Standard model

Toward an Optimum Design of an Amorphous Silicon Photovoltaic/Thermal System:Simulation and Experiments

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Journal of Thermal Science 2023年第3期32卷 947-964页

作者： REN Xiao LI Jing LIU Weixin ZHU Chuanyong PEI Gang gong liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Research Center for Sustainable Energy Technologies Energy and Environment InstituteUniversity of HullHU67RXUK Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230026China

Amorphous silicon photovoltaic/thermal(a-Si-PV/T)technology is promising due to the low power temperature coefficient,thin-film property,thermal annealing effect of the solar cells,and high conversion efficiency in *** design of a-Si-PV/T system is influenced by a number of thermodynamic,structural,and external *** analysis is useful for a good design of the system.A dynamic distributed parameter model is built and verified in this *** tests are carried *** impacts of operating temperature,mass flow rate,cover ratio of solar cells,heat transfer area,and frame shadow ratio on its performance are theoretically and experimentally *** results indicate that seven or eight copper tubes are suitable to achieve a high overall efficiency of the a-Si-PV/T *** frame and tilt angle shall avoid a shadow ratio of more than 8.3%during *** difference between power outputs at operating temperatures of 35℃and55℃in the first month is about 0.21%while it drops to less than 0.1%in the twelfth *** with conventional PVT systems,the a-Si-PV/T system benefits from a higher design temperature with a minor efficiency decrement.

关键词： amorphous silicon cell photovoltaic thermal system parametric analysis distributed parameter model frame shadow