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Catalyst grading technology for promoting the diesel hydrocracking to naphtha

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Petroleum Science 2023年第6期20卷 3798-3806页

作者： Jia-Qi Ge Peng Zhang Fa-Min Sun Ze-An Xie Zhi-Jie Wu bai-jun Liu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Petrochemical Research Institute PetroChina Company LimitedBeijing102206China Daqing Petrochemical Research Center PetroChina Company LimitedDaqing163714HeilongjiangChina Institute of Catalysis for Energy and Environment Shenyang Normal UniversityShenyang110034LiaoningChina

This paper reports the application of multi-component hydrocracking catalyst grading technology in diesel hydrocracking system to increase naphtha,and studies the influence of catalyst systems with different number of graded beds on the reaction process of diesel *** hydrocracking catalysts with different physicochemical properties as gradation components,the diesel hydrocracking reaction on catalyst systems of one-component,two-component and three-component graded beds with different loading sequences are carried out and evaluated,*** catalytic mechanism of the multi-component grading system is *** results show that,with the increase of the number of grading beds,the space velocity of reaction on each catalyst increases,which can effectively control the overreaction process;along the flow direction of feedstock,the loading sequences of catalysts with acidity decreasing and pore properties increasing can satisfy the demand of different catalytic activity for the conversion of reactant with changing composition to naphtha,which has a guiding role in the conversion of feedstock to target ***,the conversion of diesel,the selectivity and yield of naphtha all increase significantly on the multi-component catalyst *** research on the grading technology of multi-component catalysts is of great significance to the promotion and application of catalyst systems in various catalytic fields.

关键词： Grading technology Multi-component catalysts Hydrocracking Diesel Naphtha

Process Optimization and Reaction Mechanism of Removing Copper From an Fe-Rich Pyrite Cinder Using Chlorination Roasting

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Journal of Iron and Steel Research International 2013年第8期20卷 20-26页

作者： LIU Jian WEN Shu-ming CHEN Yu LIU Dan bai Shao-jun WU Dan-dan Faculty of Land Resource Engineering Kunming University of Science and Technology Dongbao District Administration of Work Safety

The aim is to remove copper from a pyrite cinder by optimizing the chlorination roasting process using re-sponse surface methodology （RSM） and the reaction mechanism of chlorination roasting based on thermodynamic calculation was discussed. A quadratic model was suggested by RSM to correlate the key parameters, namely, dos-age of chlorinating agent, roasting temperature and roasting time to the copper volatilization ratio. The results indi- cate that the model is well consistent with the experimental data at a correlation coefficient （R2） of 0.95, and the dosage of chlorinating agent and roasting temperature both have significant effects on the copper volatilization ratio. However, a roasting temperature exceeding 1170 ~C decreases the volatilization ratio. The optimum conditions for removing copper from the cinder were identified as chlorinating agent dosage at 5%, roasting temperature at i155.10 ℃ and roasting time of 10 min; under Such a conditiom a copper volatilization ratid of 95.16% Was a- chieved from the cinder. Thermodynamic calculation shows that SiO2 in the pellet plays a key role in the chlorine re-lease from calcium chloride, and the chlorine release reactions cannot occur without it.

关键词： process optimization chlorination roasting pyrite cinder removing copper

Growth of ZSM-5 crystals within hollow β-zeolite

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Chinese Chemical Letters 2011年第9期22卷 1103-1106页

作者： Qing Hu Zeng Xiang bai Jia jun Zheng Jia Qi Chen Rui Feng Li Key Laboratory of Coal Science and Technology MOE Taiyuan University of Technology Taiyuan 030024 China

A zeolite composite composed of ZSM-5 and β-zeolites has been synthesized by a procedure of the nucleation and crystallization of ZSM-5 zeolite in the hollow β-zeolite. The property of β-zeolite crystals with aluminum-poor interior and aluminum-rich outer rim results in silicon extraction favorably in the aluminum-poor bulk rather than the aluminum-rich external surface. Subsequently, alkaline treatment offl-zeolite crystals during the second-step synthesis leads to a preferential dissolution of the aluminum-poor center and the formation of hollow β-zeolite crystals. ZSM-5 zeolite crystals are therefore embedded and grown within the hollow β-zeolite. The catalytic activities of Co-Hβ, Co-HZSM-5 and Co-HZSM-5/BEA are investigated during the reaction of methane catalytic reduction NO in the presence of O2.

关键词： ZSM-5 β-Zeolite Zeolite composite

Allyl-containing Poly(aryl ether sulfone): Synthesis and Crosslinking

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Chemical Research in Chinese Universities 2011年第3期27卷 520-523页

作者： YU Yun-wu XING Yan GUO Mei-mei LIU bai-jun JIANG Zhen-hua Alan G. MacDiarmid Institute College of Chemistry JiJin University Changehun 130012 R R. China

A novel type of crosslinkable poly（aryl ether sulfone）（PAES） bearing an allyl pendant（PES-OAllyl） was synthesized by a grafting reaction of hydrophenyl-containing PAES（PES-OH） and allyl bromide. PES-OH was prepared by a demethylation reaction of a methoxyphenylated PAES（PES-OCH3） in the presence of pyridine/hydrochlo- ride. The PES-OCH3 was synthesized by an aromatic nucleophilic substitution of bis（4-chlorophenyl）sulfone and （p-methoxy）phenylhydroquinone. Both DSC and solubility investigation were used to study the crosslinking behavior of PES-OAllyl. After heat treatment, the glass transition temperature（Tg） value of PES-OAllyl sharply increased from 165 ℃ to 227 ℃. Meanwhile, PES-OAllyl changed from a soluble polymer to an insoluble thermoset. In addition, TGA（thermogravimetric analysis） result suggests that the thermal stability of the crosslinked product was improved. All the data prove that the crosslinked PES-OAllyl could be a potential solvent-resistance high-performance material.

关键词： Crosslinkable Grafting reaction Poly(aryl ether sulfone)

MMP-1 Over-expression Promotes Malignancy and Stem-Like Properties of Human Osteosarcoma MG-63 Cells In Vitro

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Current Medical Science 2018年第5期38卷 809-817页

作者： Man-li TANG Xiang-jun bai Yong LI Xiao-jing DAI Fan YANG Department of Traumatic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Orthopaedic Surgery McGovern Medical Schoolthe University of Texas Health Science Center at Houston (UTHealth)Houston77035USA Center for Stem Cell and Regenerative Medicine UTHealthHouston 77035USA Center for Regenerative Sports Medicine Steadman Philippon Research InstituteFail 81657USA Department of Pharmacology and Toxicology College of Pharmacythe University of HoustonHouston 77555USA

Osteosarcoma is the most common primary malignant bone tumor in childhood,and it maintains a high level of *** metalloproteinase-1(MMP-1)was found to contribute to cancer *** present study was to investigate the in vitro effects of MMP-1 over-expression on the proliferation,invasion,metastasis and stem-like properties of osteosarcoma MG-63 *** MG-63 cells were cultured and had a full length MMP-1 cDNA inserted by the tentiviral vector (MG-63^MMP-1+).MG-63 negative control and MG-63 blank control groups were established as ***-1 expression was detected in MG-63^MMP-1+,MG-63 negative control and MG-63 blank control cells using qPCR,Western blotting and immunofluorescence after 24h of culture. The cell proliferation assay was performed with a camera attached to a bioreactor,which was programmed to photograph five regions of each well every 10 min over a period of 48 *** cell invasion assay was conducted with Matrigel to assess the invasive potential,of MG-63 cells over 24h,the qPCR analysis to measure stem cell markers,including Oct4, Sox-2,Nanog,and Pax-7,and Western blot analysis to detect invasive and metastatic potential markers TIMP-1,VEGF and BMP2/4,after 24h of *** was used to investigate the presence of the stem cell marker Pax-7 after 24-h culture. The results showed that over-expression of MMP-1 after transfection could significantly increase minor cell proliferation and invasion (P<0.05,MG-63^MMP-1+ versus controls).Pax-7 was highly expressed in MG-63^MMP-1+ cells,with no significant changes of Oct-4,Sox-2, and Nanog observed (P<0.05).MG-63^MMP-1+ cells showed higher expression of VEGF and BMP 2/4 proteins and lower expression of TIMP-1 protein than controls (P<0.05).It was concluded that MMP-1 over-expression in MG-63 cells contributed to the proliferation, invasion,metastasis and stem-like properties of osteosarcoma *** studies should focus on in vivo effects of MMP-1 over-expression an

关键词： osteosarcoma MG-63 cells matrix metalloproteinase-1 proliferation invasion metastasis

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以竞争为标尺重构中国天然气价格市场化改革

天然气工业 2020年第5期40卷 117-125页

作者：白俊北京市燃气集团研究院北京市100011

中国目前多维度划分天然气市场化价格和非市场化价格的做法产生重叠交叉,导致以天然气基准门站价为基础的政府指导价管制体系事实上失效,引发价格不规范行为。为了推动中国天然气价格的市场化改革,在系统分析改革进程的基础上,从新的视... 详细信息

中国目前多维度划分天然气市场化价格和非市场化价格的做法产生重叠交叉,导致以天然气基准门站价为基础的政府指导价管制体系事实上失效,引发价格不规范行为。为了推动中国天然气价格的市场化改革,在系统分析改革进程的基础上,从新的视角(将天然气价格市场化分为定向、非定向两种类型),剖析了市场化改革具有的特点和存在的主要问题,进而提出了以竞争作为标尺重构天然气价格市场化改革的思路和方案。结论认为:①中国天然气价格的市场化改革具有边际上寻求突破、渐进方式推进改革、针对性进行调整、改革思路渐次成熟等特点;②市场化改革存在着政策交叉重叠导致价格管制失效、竞争性市场结构尚未完全建立、改革的协调性和同步性不够、市场监管存在差距、终端价格传导机制不畅等主要问题;③需要以竞争作为标尺重构天然气价格市场化改革,理顺既有价格市场化政策,优化天然气门站价格制度设计和适用范围,同时加快上游市场和进口环节开放,培育多元化的市场主体,推动城市燃气行业体制改革,夯实竞争环节公平竞争监管体制,深化中间管网环节改革和监管,合理界定交易平台定位,积极为向价格全面市场化平稳有序过渡做准备。

关键词：中国天然气价格市场化改革定向市场化非定向市场化竞争监管体制交易平台

Direct farm, production base, traceability and food safety in China

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Journal of Integrative Agriculture 2015年第11期14卷 2380-2390页

作者： DING Ji-ping HUANG Ji-kun JIA Xiang-ping bai jun-fei Steve Boucher Michael Carter Center for Chinese Agricultural Policy Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences College of Economics & Management Northwest A&F University College of Economics and Management China Agricultural University Agricultural and Resource Economics University of California

With the rapid growth of China＇s economy, rising demand for safety food has been accompanied by frequent food safety scandals. Given that China＇s farming is dominated by millions of small-scale farms, ensuring food safety is a major challenge facing the public and private sectors. The direct farm （DF） program, initiated in 2008, represents one of the government＇s major initiatives to modernize the distribution of fresh fruit and vegetables （FFV） and improve food safety. Under the DF program, participating national and international retailers are expected to establish more direct procurement relationships with farm communities. While it is often claimed that greater participation by retailers in the production and post-harvest processing implied the DF program will lead to improved quality, safety and traceability, systematic evidence remains elu- sive as existing studies are largely narrative, based on case studies, or theoretical inference. Little empirical evidence is available for a broader evaluation of the DF program. This paper aims to fill this gap by assessing the overall performance of a single retailer＇s DF experience with respect to the procurement and food safety of FFV. We use data from a survey of production managers of 35 DF production bases （PBs） spread across 11 provinces, 3 cities and 1 autonomous region in China. The results show a mixture of opportunities and challenges. On one hand, the DF program improves production practices and distribution channels of FFV produced on its PBs, thus facilitating the move of China＇s food system towards improved food safety compliance. On the other hand, significant heterogeneity in the traceability of food and the ability of DF to meet higher safety standards is evident both across major product categories and across household-operated vs. firm-operated PBs. The paper concludes with policy implications.

关键词： direct farm production base marketing chain traceability food safety

Flexible Blue Light Emitting Diodes Made from Dye Doped Poly (N-Vinylcarbazole) with Multilayer Structure

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Chinese Physics Letters 1997年第1期14卷 74-76页

作者： CHEN bai-jun HOU Jing-ying HUANG Jing-song LIU Shi-yong State Key Laboratory on Integrated Optoelectronics Jilin UniversityChangchun 130023

Flexible blue light emitting diodes(LEDs)were fabricated by using poly(N-vinylcarbazole)(PVK)doped with high fluorescence dye,1,1,4,4-tetraphen1-1,3-butadiene(TPB),as a emitter layer,a layer of tris(8-quinolino1ato)aluminum(Ⅲ)(Alq3)as an electron-transporting layer,and a layer of 2-(4-biphenylyl)-5-(4-tertbutypheny)-1-3,4-oxadiazole(PBD)as hole-blocking layer;a cell structure of flexible substrate/indium-tin-oxide/PVK:TPB/PBD/Alq3/Al was *** this cell structure,carrier injection from the electrodes to the doped PVK layer and concomitant electroluminescence from doped PVK were observed at room temperature with dcbias voltage of *** emission peaks at about *** kind of LED is about 200μm thick and can be curled or bent repeatedly at sharp angles without failure.

关键词： emitter layer repeatedly

Na^+ and Water Uptake in Relation to the Radial Reflection Coefficient of Root in Arrowleaf Saltbush Under Salt Stress

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Journal of Integrative Plant Biology 2007年第9期49卷 1334-1340页

作者： Xin-Fu bai Jian-jun Zhu Ping Zhang Yan-Hua Wang Li-Qun Yang Lei Zhang College of Life Sciences Ludong University Yantai 264025 China

The response of halophyte arrowleaf saltbush （Atriplex triangularis Willd） plants to a gradient of salt stress were investigated with hydroponically cultured seedlings. Under salt stress, both the Na^＋ uptake into root xylem and negative pressures in xylem vessels increased with the elevation of salinity （up to 500 mol/m^3） in the root environment. However, the increment in negative pressures in root xylem far from matches the decrease in the osmotic potential of the root bathing solutions, even when the osmotic potential of xylem sap is taken into consideration. The total water potential of xylem sap in arrowleaf saltbush roots was close to the osmotic potential of root bathing solutions when the salt stress was low, but a progressively increased gap between the water potential of xylem sap and the osmotic potential of root bathing solutions was observed when the salinity in the root environment was enhanced. The maximum gap was 1.4 MPa at a salinity level of 500 mol/m^3 without apparent dehydration of the tested plants. This discrepancy could not be explained with the current theories in plant physiology. The radial reflection coefficient of root in arrowleaf saltbush decreased with the enhanced salt stress was and accompanied by an increase in the Na^＋ uptake into xylem sap. However, the relative Na^＋ in xylem exudates based on the corresponding NaCl concentration in the root bathing solutions showed a tendency of decrease. The results showed that the reduction in the radial reflection coefficient of roots in the arrowleaf saltbush did not lead to a mass influx of NaCl into xylem when the radial reflection coefficient of the root was considerably small; and that arrowleaf saltbush could use small xylem pressures to counterbalance the salt stresses, either with the uptake of large amounts of salt, or with the development of xylem pressures dangerously negative. This strategy could be one of the mechanisms behind the high resistance of arrowleaf saltbush plants to

关键词： anti-osmosis arrowleaf saltbush (Atriplex triangularis Willd) radial reflection coefficient of root salt stress xylem pressure