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Science China Earth Sciences 2016年第8期59卷 1642-1651页

作者： WANG XiaoMin GUAN Ying CAI HuiYang Sandrine COSTAMAGNO ZHANG LiMin xu chunhua GAO Xing Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China University of Chinese Academy of Sciences Beijing 100049 China TRACES CNRS Toulouse 31058 France Guizhou Provincial Museum Guiyang 550001 China

Laoya Cave is a long-term occupation site of Late Paleolithic humans in the Yunnan-Guizhou Plateau, southwest China, where abundant lithic, bone materials were recovered. Dating by the AMS technique showed a significant depositional process during marine isotope stage(MIS) 3/2. In this study, the species spectrum was presented from the perspective of zooarchaeology and the mortality profile of large Cervidae was examined to help increase our understanding of the subsistence strategy of local people dealing with climate and environmental changes. The main part of the diet was focused on large Cervidae, and the dominance of Ungulates indicates effective management of the cave and local fauna. On the other hand, the mortality profiles of large Cervidae varied correspondingly with climate change. The evidence indicates a specialized hunting strategy that was also flexible, depending on the prevailing climate and environment.

关键词： Cervidae Late Paleolithic Southwest China MIS 3 Zooarchaeology Survival strategy

Preparation and characterization of β-FeOOH-coated sand and its adsorption of Cr（VI） from aqueous solutions

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Frontiers of Environmental Science & Engineering 2012年第4期6卷 455-462页

作者： chunhua xu Dandan CHENG Baoyu GAO Zhilei YIN Qinyan YUE Xian ZHAO Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityJinan 250100China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China

Batch adsorption experiments were conducted to explore the adsorption of Cr（VI） in aqueous solutions by fl-FeOOH-coated sand. We investigated the key factors which affected the adsorption process such as adsorbent dosage, initial pH, initial Cr（VI） ion concentration, contact time and temperature. The uptake of Cr（VI） was very rapid and 44.3%, 51.6%, 58.9% of the adsorption happened during the first 180minutes at 293K, 303K and 313K, respectively. The pseudo-second-order rate equation successfully described the adsorption kinetics. To study the adsorption isotherm, two equilibrium models, the Langmuir and Freundlich isotherms, were adopted. At 293K, 303K and 313K, the adsorption capacities obtained from the Langmuir isotherm were 0.060, 0.070 and 0.076 mg Cr（VI） per gram of the adsorbent, respectively. Thermodynamic parameters such as the change of energy, enthalpy and entropy were calculated using the equilibrium constants. The negative value of AGO and the positive value of △H^0 showed that the adsorption of Cr（VI） in aqueous solutions by β-FeOOH-coated sand was spontaneous, endothermic and occurred by physisorption.

关键词： β-FeOOH-coated sand Cr(VI) adsorption isotherm kinetics

The high catalytic activity and strong stability of 3%Fe/AC catalysts for catalytic wet peroxide oxidation of m-cresol: The role of surface functional groups and FeO_(x) particles

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Chinese Journal of Chemical Engineering 2022年第4期35卷 105-114页

作者： Peiwei Han chunhua xu Yamin Wang Chenglin Sun Huangzhao Wei Haibo Jin Ying Zhao Lei Ma Beijing Key Laboratory of Fuels Cleaning and Advanced Catalytic Emission Reduction Technology/College of Chemical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityQingdao 266237China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

FeO;supported on activated carbon(AC) has been shown to be an ideal catalyst for catalytic wet peroxide oxidation(CWPO) due to its high CWPO reaction activity and stability. Although there have been some studies on the mechanism of Fe/AC catalysis in CWPO, the specific contribution of each component(surface oxygen groups and FeOxon AC) inside an Fe/AC catalyst and their corresponding reaction mechanism remain unclear, and the reaction stability of CWPO catalysts has rarely been discussed. Then the optimal CWPO catalyst in our laboratory, 3%Fe/AC, was selected.(1) By removing certain components on the AC through heat treatment, its contribution to the reaction and the corresponding reaction mechanism were investigated. With the aid of temperature-programmed desorption–mass spectrometry(TPD–MS) and the CWPO reaction, the normalized catalytic contributions of components were shown to be: 37.3%(carboxylic groups), 5.3%(anhydride), 19.3%(ether/hydroxyl),-71.4%(carbonyl groups) and 100%(FeOx),respectively. DFT calculation and EPR analysis confirmed that carboxylic groups and Fe_(2)O_(3) are able to activate the H_(2)O_(2) to generate·OH.(2) The catalysts at were characterized at different reaction times(0 h, 450 h, 900 h, 1350 h, and 1800 h) by TPD–MS and M?ssbauer spectroscopy. Results suggested that the number of carboxylic goups gradually increased and the size of paramagnetic Fe_(2)O_(3) particle crystallites gradually increased as the reactions progressed. The occurrence of strong interactions between metal oxides and AC was also confirmed. Due to these effects, the strong stability of 3%Fe/AC was further improved. Therefore, the reasons for the high activity and strong stability of 3%Fe/AC in CWPO were clearly shown. We believe that this work provides an idea of the removal of cresols from wastewater into the introduction to show the potential applications of CWPO.

关键词： Catalytic wet peroxide oxidation Fe/AC catalyst Surface functional groups Reaction mechanism

Privacy-Preserving Trust Negotiation with Hidden Credentials and Hidden Policies in a Multi-Party Environment

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Wuhan University Journal of Natural Sciences 2008年第5期13卷 553-556页

作者： GUO Shanqing WEI Juan ZHANG chunhua xu Qiuliang School of Computer Science and Technology ShandongUniversity Jinan 250101 Shandong China

Until now, there are numerous protocols that can achieve privacy-preserving trust negotiation between two parties involved, but there is no effective privacy-preserving trust negotiation schemes proposed between multi-users. In this paper, a privacy-preserving trust negotiation scheme with multi-parties is proposed, which can protect their credentials and access control policies during the procedure for establishing the trust between multi-strangers, and its privacy-preserving ability also is proved. These works extend the trust negotiation mechanism to multi-users, which can be thought as a substantial extension of the state-of-the-art in privacy-preserving trust negotiations between two parties involved.

关键词： trust negotiation credential policy privacy-preserving

New insight into the mechanism of DNA polymerase I revealed by single-molecule FRET studies of Klenow fragment

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Chinese Physics B 2022年第8期31卷 705-708页

作者： Rokshana Parvin Qi Jia Jianbing Ma chunhua xu Ying Lu Fangfu Ye Ming Li Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We use single-molecule FRET and newly-developed D-loop techniques to investigate strand displacement activity of Klenow fragment(exo-)of DNA polymerase I in DNA sequences rich in guanine and cytosine(GC)*** find that there exist in the FRET traces numerous ascending jumps,which are induced by the backsliding of Klenow fragment on DNA *** measurements show that the probability of backsliding is closely related to the GC-richness and d NTP concentration:increasing the GC-richness leads to an increase in the backsliding probability,and increasing the d NTP concentration however leads to a decrease in the backsliding *** results provide a new insight into the mechanism of DNA polymerase I.

关键词： smFRET Klenow fragment GC-richness strand displacement

Fine mapping of cisc(t),a gene for cold-induced seedling chlorosis,and identification of its candidate in rice

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Chinese Science Bulletin 2010年第27期55卷 3149-3153页

作者： LAN Tao WANG Bin LING QiuPing xu chunhua TONG ZhiJun LIANG KangJing DUAN YuanLin JIN Jing WU WeiRen Key Laboratory of Ministry of Education for Genetics Breeding and Multiple Utilization of Crops Fuzhou 350002 China Fujian Provincial Key Laboratory of Rice Molecular Marker-Assisted Breeding Fuzhou 350002 China

The seedlings of indica rice cultivar Dular are susceptible to chlorosis under low temperature *** previous studies indicated that low temperature-induced seedling chlorosis is controlled by a recessive gene,located between SSR markers RM257 and RM242,on the long arm of chromosome *** temporarily named the gene cisc(t).Using a large F2 population derived from a cross between Dular and the japonica cultivar Lemont,which displays a normal green color at low temperatures,cisc(t)was fine mapped to within a 12-kb *** is only one annotated gene in this interval,which encodes a pentatricopeptide repeat(PPR)*** analysis indicated that 8 bases were deleted at the 60th base in the Dular allele,resulting in a frame-shift mutation and loss of function of the *** is consistent with the chlorosis mutant phenotype of *** addition,previous studies have shown that many chlorosis mutants of seedlings are related to PPR ***,we presume that the PPR gene is the candidate for cisc(t).

关键词：黄化现象隐性基因 CISC 精细定位幼苗鉴定水稻低温条件

Clinical significance of serum and tumor tissue transthyretin expression in surgically resected non-small cell lung cancer

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Clinical significance of serum and tumor tissue transthyreti...

Development of "Green" Rubber Additives

2022CCTB中国肿瘤标志物学术大会暨中国整合肿瘤学大会暨第十六届肿瘤标志物青年科学家论坛暨中国肿瘤标志物产业创新大会

作者： chunhua xu Nanjing Chest Hospital

Objective:Transthyretin(TTR) is a traditional biomarker for nutritional and *** present study was conducted to explore the clinical value of TTR in serum and tumor tissue in patients with surgically resected non-small cell lung cancer(NSCLC).Methods:TTR expression levels were determined in paraffin-embedded NSCLC tissue specimens using *** TTR expression levels were measured from patients with lung cancer and healthy controls using enzyme-linked immunosorbent assay(ELISA).Results:The expression levels of TTR were significantly higher in lung cancer tissues than in paracancerous tissues,and TTR expression was significantly associated with TNM stage(P=0.002) and lymph node metastasis(P=0.032).Multivariate analysis revealed that increased expression of TTR was an independent risk factor for overall survival(P=0.012)and progression-free survival(P=0.011) in NSCLC *** expression levels of TTR in serum from lung cancer patients were lower than those of healthy controls(P=0.002).A high expression of TTR in tumor tissue was associated with a higher serum level(r=0.799,P=0.001).Conclusions:TTR expression is upregulated in lung cancer patients,and its expression was correlated with poor prognosis in NSCLC patients.

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China Chemical Reporter 2010年第9期21卷 29-31页

作者： xu chunhua, China Rubber Industry Association

After 58 years of development, China hasbecome the world’s largest producer andconsumer of rubber additives. In 2009,China produced around 660 000 tons ofrubber additives (accounting for more than50% of the world’s total), achieving a totalindustrial output value of about RMB12billion. Thirty percent of the rubber additivesthat China produced were ***’s output of antioxidant 4020, acceleratorNS, scorch agent CTP and silane couplingagent Si-69 occupied leading

关键词： rubber additives producer accounting exported anti

Better Tomorrow of China Rubber Chemicals Industry

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中国橡胶 2011年第16期27卷 2-5页

作者： xu chunhua Vice President of CRIA

*** of China Rubber Chemicals Industry During the "11th Five-Year Plan" period,China rubber Chemicals industry fully implemented the development guideline of "Adhering to science and technology development,developing green chemistry with environmental protection,safety and energy conservation as the core,and building enterprise and world brands".With the great support of the state,China has become a world production and consumption power of rubber Chemicals with the national output of 660,000 tons in 2009 and gross industrial output value of about 12 billion *** is estimated that,in 2010,the national output will be 750,000 tons,the

关键词： Pro over Better Tomorrow of China Rubber Chemicals Industry TMTD high

Characterization of genetic humanized mice with transgenic HLA DP401 or DRA but deficient in endogenous murine MHC classⅡgenes upon Staphylococcus aureus pneumonia

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Animal Models and Experimental Medicine 2023年第6期6卷 585-597页

作者： Feng Li Bowen Niu Lingling Liu Mengmin Zhu Hua Yang Boyin Qin Xiuhua Peng Lixiang Chen chunhua xu Xiaohui Zhou Department of Laboratory Animal Science Shanghai Public Health Clinical CenterShanghaiChina

Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”*** DQ and HLA DR humanized mice have been used as a small animal model to study the role of two molecules during *** ***,the contribution of HLA DP to *** infection is unknown ***:In this study,we have produced HLA DP401 and HLA DRA0101 humanized mice by microinjection of C57BL/6J ***-floxed IAβ+/-mice were crossbred with Ella-Cre and further crossbred with HLA DP401 or HLA-DRA0101 humanized *** several rounds of traditional crossbreeding,we finally obtained HLA DP401-IAβ-/-and HLA DRA-IAβ-/-humanized mice,in which human DP401 or DRA0101 molecule was introduced into IAβ-/-mice deficient in endogenous murine MHC classⅡmolecules.A transnasal infection murine model of *** pneumonia was induced in the humanized mice by administering 2×108CFU of *** Newman dropwise into the nasal *** immune responses and histopathology changes were further assessed in lungs in these infected ***:We evaluated the local and systemic effects of *** delivered intranasally in HLA DP401-IAβ-/-and HLA DRA-IAβ-/-transgenic *** Newman infection significantly increased the m RNA level of IL 12p40 in lungs in humanized *** increase in IFN-γand IL-6 protein was observed in HLA DRA-IAβ-/-*** observed a declining trend in the percentage of F4/80+macrophages in lungs in HLA DP401-IAβ-/-mice and a decreasing ratio of CD4+to CD8+T cells in lungs in IAβ-/-mice and HLA DP401-IAβ-/-mice.A decreasing ratio of Vβ3+to Vβ8+T cells was also found in the lymph node of IAβ-/-mice and HLA DP401-IAβ-/-*** Newman infection resulted in a weaker pathological injury in lungs in IAβ-/-genetic background ***:These humanized mice will be an invaluable mouse model to resolve the pathological mechanism of *** pneumonia and study what role DP molecule plays in *** in

关键词： HLA DP401 HLA-DRA humanized mice MHC II Staphylococcus aureus pneumonia transgene