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Microbial Community Structure and Enzyme Activities in a Sequence of Copper-Polluted Soils

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Pedosphere 2011年第2期21卷 164-169页

作者： GE chao-rong ZHANG Qi-Chun Laboratory of Clinical Microbiology The First Affiliated Hospital of College of Medicine Zhejiang University Hangzhou 310003(China) Zhejiang Provincial Key Laboratory of Subtropic Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

The microbial community structure and enzyme activities of seven paddy soils with different Cu concentrations were investigated in the vicinity of a Cu smelter in Fuyang County, Zhejiang Province in Southeast China. The microbial community structure was analyzed using the phospholipid fatty acid （PLFA） and multiplex-terminal restriction fragment length polymorphism （M-TRFLP） techniques. There was no clear dose-response relationship between Cu pollution and soil enzyme activity except for urease. Both PLFA and M-TRFLP methods showed that Cu contamination had a large effect on the soil microbial community structure. PLFA indicators of Gram-positive bacteria （16：0i, 15：0i） and fungi （18：2w6,9） relatively decreased with increasing Cu concentration, whereas indicators of Gram-negative bacteria （19：0cy, 16：1w7） increased. The M-TRFLP results suggested that there was a dose-dependent response between Cu pollution and bacterial community or fungal community. The fungal community was more sensitive to Cu pollution than the bacterial community. Therewere no significant differences in archaeal community structure between the different Cu pollution plots and axchaea might be more tolerant to Cu pollution than both bacteria and fungi.

关键词： axchaea bacteria fungi multiplex-terminal restriction fragment length polymorphism phospholipid fatty acid

A THREE-SEGMENT HYDRAULIC MODEL FOR ANNULAR CUTTINGS TRANSPORT WITH FOAM IN HORIZONTAL DRILLING

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Journal of Hydrodynamics 2008年第1期20卷 67-73页

作者： CHENG rong-chao WANG Rui-he College of Petroleum Engineering China University of Petroleum（East China） Dongying 257061 China

Through mechanical analysis, an improved hydraulic model for annular cuttings transport with foam was established for horizontal drilling. Based on the two critical inclination angles, the entire well was divided into three segments. The Bagnold stress, generalized power law rheological model and modified hindered particle settling velocity in foam fluid were adopted in the model to improve the simulation accuracy. The proposed model allows more precise prediction of cuttings transport property in the whole range of well inclination angle. Model performance was examined via case study and experimental data. Simulation results given by the propulsion iteration and trial-and-error method agree well with in-situ horizontal well drilling practice for the case study, and the comparison between the model prediction and Capo’s experimental data shows satisfactory agreement.

关键词： horizontal well foam fluid drilled cuttings hydraulic model well inclination angle

ECC-Based RFID Authentication Protocol

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Journal of Electronic Science and Technology 2020年第4期18卷 320-329页

作者： Xing-Chun Yang Chun-Xiang Xu chao-rong Li Department of Computer Science and Technology Sichuan Police CollegeLuzhou 646000 School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 Department of Computer Science and Information Engineering Yibin UniversityYibin 644000

The radio frequency identification(RFID)technology has been widely used so far in industrial and commercial *** develop the RFID tags that support elliptic curve cryptography(ECC),we propose a scalable and mutual authentication protocol based on *** also suggest a tag privacy model that provides adversaries exhibiting strong abilities to attack a tag’s *** prove that the proposed protocol preserves privacy under the privacy model and that it meets general security *** with other recent ECCbased RFID authentication protocols,our protocol provides tag privacy and performs the best under comprehensive evaluation of tag privacy,tag computation cost,and communications cost.

关键词： Elliptic curve cryptography radio frequency identification(RFID) authentication protocol privacy

PS-HQ:More convenient in situ polymeric cocatalyst for the PdC1_2-catalyzed acetalization in supercritical carbon dioxide

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Chinese Chemical Letters 2007年第8期18卷 969-972页

作者： Zhao Yang Wang Huan Feng Jiang chao rong Qi Yan Xia Shen Shao rong Yang College of Chemistry South China University of Technology Guangzhou 510640 China Department of Chemistry South China Normal University Guangzhou 510006 China

Polystyrene-supported hydroquinone （PS-HQ） is presented as an in situ polymeric cocatalyst to replace polystyrenesupported benzoquinone （PS-BQ） in the PdCl2-catalyzed acetalization of methyl acrylate with methanol in supercritical carbon dioxide （scCO2） under oxygen atmosphere. Due to deletion of H2O2 oxidation step, PS-HQ is more convenient and relatively inexpensive.

关键词： Palladium chloride Polymeric supported catalyst Hydroquinone Oxidation Wacker reaction Molecular oxygen

Lymphocyte-to-monocyte ratio effectively predicts survival outcome of patients with obstructive colorectal cancer

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World Journal of Gastroenterology 2019年第33期25卷 4970-4984页

作者： Xian-Qiang Chen chao-rong Xue Ping Hou Bing-Qiang Lin Jun-rong Zhang Department of General Surgery(Emergency Surgery) Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Immunotherapy Institute Fujian Medical UniversityFuzhou 350122Fujian ProvinceChina

BACKGROUND Obstructive colorectal cancer(OCC)is always accompanied by severe complications,and the optimal strategy for patients with OCC remains *** from emergency surgery(ES),self-expandable metal stents(SEMS)as a bridge to surgery(BTS),could increase the likelihood of primary ***,the stent failure and related complications might give rise to a high recurrence *** studies have focused on the indications for either method,and the relationship between preoperative inflammation indexes and the prognosis of OCC is still *** To explore the indications for ES and BTS in OCCs based on preoperative inflammation *** One hundred and twenty-eight patients who underwent ES or BTS from 2008 to 2015 were *** operating characteristic(ROC)curve analysis was used to define the optimal preoperative inflammation index and its cutoff ***–Meier analyses and Cox proportional hazards models were applied to assess the association between the preoperative inflammation indexes and the survival outcomes[overall survival(OS)and disease-free survival(DFS)].Stratification analysis was performed to identify the subgroups that would benefit from ES or *** OS and DFS were comparable between the ES and BTS groups(P>0.05).ROC curve analysis showed derived neutrophil-to-lymphocyte ratio(dNLR)as the optimal biomarker for the prediction of DFS in ES(P<0.05).Lymphocyte-tomonocyte ratio(LMR)was recommended for BTS with regard to OS and DFS(P<0.05).dNLR was related to stoma construction(P=0.001),pneumonia(P=0.054),and DFS(P=0.009)in *** was closely related to lymph node invasion(LVI)(P=0.009),OS(P=0.020),and DFS(P=0.046)in the BTS *** was an independent risk factor for ES in both OS(P=0.032)and DFS(P=0.016).LMR affected OS(P=0.053)and DFS(P=0.052)in the BTS *** could differentiate the OS between the ES and BTS groups(P<0.05).CONCLUSION Preoperative dNLR and LMR could predict OS and DFS in pat

关键词： Inflammation indexes Emergency surgery Self-expanding metal stent insertion as a bridge to surgery Obstructive colorectal cancers

SYNTHESIS AND CHARACTERIZATION OF A NOVEL ALCOHOL-SOLUBLE POLYORGANOSILOXANE CONTAINING AMINO SIDE GROUPS

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Chinese Journal of Polymer Science 2001年第1期19卷 97-102页

作者： Chun-qing Liu Yang Liu Zhong-rong Shen Ping Xie rong-ben Zhang chao-bin He Tai-shung Chung PCLCC Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China PCLCCCenter for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Institute of Materials Research and Engineering National University of Singapore Singapore 119260 Institute of Materials Research and Engineering National University of Singapore Singapore 119260

A novel alcohol-soluble polyorganosiroxane containing amino side groups, poly[3-(4-aminophenoxy)-aminophenoxy) propylmethylsiloxane] (2), was first prepared by the reduction of nitro groups on 4-nitrophenoxypropyl side chains of poly[3-(4-nitrophenoxy)propylmethylsiloxane] (1). The reaction proceeded easily with nearly 100% conversion. The synthesized alcohol-soluble polymer 2, which has potential application as a precursor for preparing advanced functional polymers, was characterized by FTIR, H-1-NMR, C-13-NMR, Si-29-NMR, VPO and GPC, respectively.

关键词： alcohol-soluble polyorganosiloxane reduction characterization

Bioaccumulation of Lanthanum and Its Effect on Growth of Maize Seedlings in a Red Loamy Soil

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Pedosphere 2006年第6期16卷 799-805页

作者： HU Xin WANG Xiao-rong WANG chao State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science Nanjing University Nanjing 210093 （China） School of Environmental Science and Engineering Hohai University Nanjing 210098 （China）

Through a pot culture lanthanum nitrate was applied to maize seedlings grown in a red loamy soil to investigate the physiological and toxic effects of added La on the growth of crop seedlings and La bioaccumulation to help understand the environmental chemistry behaviors of rare earth element as fertilizers in soils. Compared to the control, La concentrations in shoots and especially in roots of maize seedlings increased with an increase of La in the soil. Also, with added concentrations of La≥0.75 g La kg-1 soil and≥0.05 g La kg-1 soil, the dry weight of shoots and roots of maize seedlings was significantly reduced (P≤0.05), respectively, compared with the control. Additionally, La≥0.5 g kg-1 in the soil significantly inhibited (P≤0.05) primary root elongation. Roots were more sensitive to La stress than shoots and thus could be used as a biomarker to La stress. Overall, in the red loamy soil studied, La had no significant beneficial effects on the growth of maize at the added La levels above 0.1 g kg-1 soil.

关键词： bioaccumulation growth lanthanum maize seedlings red loamy soil

Preparation of Konjac Glucomannan and Acrylamide Grafted Konjac Glucomannan

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Wuhan University Journal of Natural Sciences 1999年第4期4卷 459-462页

作者： Xiao chao-bo Gao Shan-jun Li Guo-rong Zhang Qun-chao Wuhan University College of Chemistry and Environmental Science Wuhan China (GRID:grid.49470.3e) (ISNI:***)

Konjac glucomannan (KGM) with good water solubility was extracted and purified by a cheap and simple method including fat-extraction, protein-extraction, decolouring, centrifuge, precipitate and other procession from tubers of amorphophallus riveiri. Acrylamide grafted konjac glucomannan (AKGM) was prepared in the presence of Ce(IV) serving as initiator in order to elucidate its molecular weight. Results from the measurements of capillary viscosity by figuring out the specific viscosity and applying to Mark-Howink equation showed that the viscosity-average molecular weight of acrylamide grafted konjac glucomannan was about 9.58×105.

关键词： Konjac glucomannan extract graft

Plugging performance and mechanism of an oil-absorbing gel for lost circulation control while drilling in fractured formations

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Petroleum Science 2022年第6期19卷 2941-2958页

作者： Ying-Rui Bai Li-Yao Dai Jin-Sheng Sun Guan-Cheng Jiang Kai-He Lv rong-chao Cheng Xiao-Sen Shang School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina CNPC Engineering Technology R&D Company Limited Beijing102206China College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China

Lost circulation of drilling fluid is one of the most common engineering problems in the drilling process of fractured *** this study,an oil-absorbing polymer gel synthesized using compound monomers with rigid and flexible chains was applied to control the oil-based drilling fluid loss while *** microstructure,oil-absorbing performance,and plugging performance the gel was investigated.A large number of dense pores on the surface of the gel were observed,which allowed the oil molecules to enter the internal space of the *** initial oil absorption capacity of the gel was fast,and it increased with the increase in the temperature and decrease in the particle size,reaching 20.93 g/g at140℃.At a high temperature of 140℃,the bearing pressure capacity of the gel formula containing particles of different particle sizes reached 7.6 MPa for a fracture of a width of 3 mm,showing that the oil-absorbing gel have excellent plugging performance at high *** mechanism of the gel was investigated through visualized fracture plugging *** show that the dynamic migratio n,particle-swelling,particle-bridging,particle-aggregation,deformation-filling,and compaction-plugging contribute to the whole lost circulation control process,reflecting that the plugging performance can be effectively enhanced by improving the aggregation and filling degrees of the gel with different particle sizes.

关键词： Lost circulation Oil-absorbing gel Oil absorption capacity Plugging mechanism Fractured formation