20 results match your criteria: "Southwest China University[Affiliation]"

Health assessment of important tributaries of Three Georges Reservoir based on the benthic index of biotic integrity.

Sci Rep

October 2020

Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Life Sciences, Southwest China University, No. 2 Tiansheng Road, Beibei District, Chongqing, 400715, China.

China's Three Gorges Reservoir (TGR) is the largest water conservancy project in the world, and plays a significant role in flood control and water transport. To study the health status of the tributaries of TGR, we set up 175 sampling sites, including 15 reference sites and 160 impaired sites on 36 important tributaries of TGR, and collected zoobenthos at these sampling sites. We selected 26 candidate metrics, analyzed them in terms of the distribution range, discriminant ability and correlation.

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An integrated material metabolism model for stocks of urban road system in Beijing, China.

Sci Total Environ

February 2014

State Key Laboratory of Urban & Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China.

Rapid urbanization has greatly altered the urban metabolism of material and energy. As a significant part of the infrastructure, urban roads are being rapidly developed worldwide. Quantitative analysis of metabolic processes on urban road systems, especially the scale, composition and spatial distribution of their stocks, could help to assess the resource appropriation and potential environmental impacts, as well as improve urban metabolism models.

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[Effects of water stress and nitrogen nutrition on regulation of Catharanthus roseus alkaloids metabolism].

Zhongguo Zhong Yao Za Zhi

May 2012

Key Laboratory of Ecoenvironments in Three Gorges Reservoir Region, Ministry of Education, School of Life Science, Southwest China University, Chongqing 400715, China.

Objective: Under various drought conditions and nitrogen application, the content of vindoline, catharanthine, vincristine and vinblastine in the leaf of Catharanthus roseus were illustrated to improve the content of alkaloid theoretically.

Method: Six groups were set in the experiment, which included: CK (natural control), CN (natural control + nitrogen), LK (low drought), LN (low drought + nitrogen), HK (high drought), HN (high drought + nitrogen) to discuss the change characteristics of total nitrogen, the activity of alkaline POD and TDC, the content of four alkaloids under the different conditions were measured.

Result: Under LK condition, the activity of POD, TDC were enhanced.

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[Effect of enhanced UV-B radiation on metabolism and berberine content of Coptis chinensis].

Zhongguo Zhong Yao Za Zhi

November 2011

Key Laboratory of Ecoenvironments in Three Gorges Reservoir Region (Ministry of Education), School of Life Science, Southwest China University, Chongqing 400715, China.

Objective: To reveal the response of content berberine in root of Coptis chinensis to different intensity of UV-B radiation, and provide the theory basis for promoting the content of berberine.

Method: Four groups of UV-B radiation were set in the experiment which included: natural light control (0 W x m(-2)), UL (0.05 W x m(-2)), UM (0.

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[Effects of drought stress and re-watering on the active oxygen scavenging system of Cupressus funebris seedlings in Karst area].

Ying Yong Sheng Tai Xue Bao

November 2011

Ministry of Education Key Laboratory of Eco-environment in Three Gorges Reservoir Region, Southwest China University, Chongqing 400715, China.

This paper studied the active oxygen scavenging system of Cupressus funebris seedlings under drought condition and the recovery capability of the system after re-watering, aimed to understand the adaptation mechanisms of C. funebris to the 'drought and re-watering' environment in Karst area. With the increasing time of drought stress, the seedling's relative water content (RWC) decreased, soluble protein concentration increased first and decreased then, and malondialdehyde (MDA) content increased consistently.

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[Effect of enhanced UV-B radiation on photosynthetic structure and photosynthetic characteristics of Mentha piperita].

Zhongguo Zhong Yao Za Zhi

December 2009

Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Life Science, Southwest China University, Chongqing 400715, China.

Objective: To reveal the effects of UV-B radiation on the growth of medical plant Mentha piperita, simulate an enhanced UV-B radiation and evaluate intensity of radiation on the photosynthesis of M. piperita.

Method: Three different levels of UV-B radiation were set in the experiment which included: natural light control (0 W x m(-2)), light UV-B radiation stress (0.

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In an acid medium solution, proteins such as bovine serum albumin, human serum albumin, ovalbumin, hemoglobin, lysozyme, gamma-globulin, alpha-chymotrypsin and papain could react with [PdI(4)](2-) by virtue of electrostatic attraction and hydrophobic force to form ion-association complexes. As a result, the resonance Rayleigh scattering (RRS) and resonance nonlinear scattering such as second-order scattering (SOS) and frequency doubling scattering (FDS) intensities were enhanced greatly and new scattering spectra appeared. The maximum scattering peaks of RRS, SOS and FDS were at 367, 720 and 370 nm, respectively.

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Resonance Rayleigh scattering spectra, non-linear scattering spectra of tetracaine hydrochloride-erythrosin system and its analytical application.

Spectrochim Acta A Mol Biomol Spectrosc

January 2009

School of Chemistry and Chemical Engineering, Southwest China University, Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, Chongqing 400715, PR China.

The interaction between erythrosine (ET) and tetracaine hydrochloride (TA) was studied by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS) combining with absorption spectrum. In a weak acidic medium of Britton-Robinson (BR) buffer solution of pH 4.5, erythrosine reacted with tetracaine hydrochloride to form 1:1 ion-association complex.

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Study on immunosensor based on gold nanoparticles/chitosan and MnO2 nanoparticles composite membrane/Prussian blue modified gold electrode.

Bioprocess Biosyst Eng

April 2009

Chongqing Key Laboratory of Analytical Chemistry, College of Chemistry and Chemical Engineering, Southwest China University, 400715, Chongqing, People's Republic of China.

A novel and convenient immunosensor, based on the electrostatic adsorption characteristics between the positively charged MnO(2) nanoparticles (nano-MnO(2)) and chitosan (CS) composite membrane (nano-MnO(2) + CS) and the negatively charged prussian blue (PB), was prepared for the detection of carcinoembryonic antigen (CEA). Firstly, PB was electro-deposited on the surface of the gold electrode in the constant potential, and then nano-MnO(2) + CS was adsorbed onto PB-modified electrode surface. Subsequently, Gold nanoparticles (nano-Au) were electro-deposited on the nano-MnO(2) + CS-modified electrode to immobilize antibody CEA (anti-CEA).

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Study on the interaction between palladium(II)-lincomycin chelate and erythrosine by absorption, fluorescence and resonance Rayleigh scattering spectra and its analytical applications.

Luminescence

April 2009

School of Chemistry and Chemical Engineering, Southwest China University, Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education Chongqing 400715, People's Republic of China.

In pH 5.0-5.4 HAc-NaAc buffer solution, lincomycin (Linco) reacted with Pd(II) to form 1:1 cationic chelate, which could further react with erythrosine (Ery) to form 1:1 ion-association complexes (Pd-Linco)Ery.

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When gold nanoparticles were being prepared by sodium citrate reduction method, citrate anions self-assembled on the surface of gold nanoparticles to form supermolecular complex anions with negative charges, and protonated raloxifene (Ralo) was positively charged and could bind with the complex anions to form larger aggregates through electrostatic force and hydrophobic effects, which could result in the remarkable enhancement of the resonance Rayleigh scattering intensity (RRS), and the appearance of new RRS spectra. At the same time, the second-order scattering (SOS) and frequency-doubling scattering (FDS) intensities were also enhanced. The maximum wavelengths were located near 370 nm for RRS, 520 nm for SOS, and 350 nm for FDS, respectively.

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In pH 4.4-4.5 Britton-Robinson (BR) buffer solution, fluoroquinolone antibiotics (FLQs) including ciprofloxacin (CIP), norfloxacin (NOR), levofloxacin (LEV) and lomefloxacin (LOM) could react with erythrosine (Ery) to form 1:1 ion-association complexes, which not only resulted in the changes of the absorption spectra and the quenching of fluorescence, but also resulted in the great enhancement of resonance Rayleigh scattering (RRS).

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Investigation of the electrochemical and electrocatalytic behavior of positively charged gold nanoparticle and L-cysteine film on an Au electrode.

Anal Chim Acta

July 2007

Chongqing Key Laboratory of Analytical Chemistry, College of Chemistry and Chemical Engineering, Southwest China University, Chongqing 400715, China.

Positively charged gold nanoparticle (positively charged nano-Au), which was prepared, characterized by xi-potential and transmission electron microscopy (TEM) was used in combination with L-cysteine to fabricate a modified electrode for electrocatalytic reaction of biomolecules. Compared with electrodes modified by negatively charged gold nanoparticle/L-cysteine, or L-cysteine alone, the electrode modified by the positively charged gold nanoparticle/L-cysteine exhibited excellent electrochemical behavior toward the oxidation of biomolecules such as ascorbic acid, dopamine and hydrogen peroxide. Moreover, the proposed mechanism for electrocatalytic response of positively charged gold nanoparticle was discussed.

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Flow-injection chemiluminescence sensor for determination of isoniazid in urine sample based on molecularly imprinted polymer.

Spectrochim Acta A Mol Biomol Spectrosc

February 2007

Institute of Analytical Science, Department of Chemistry, Southwest China University, Beibei, Chongqing 400715, PR China.

In this paper, molecularly imprinted polymer (MIP) of isoniazid is synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of isoniazid template molecules. A novel flow injection chemiluminescence sensor for isoniazid determination is developed by packing the isoniazid-MIP into the flow cell as recognition elements. Isoniazid could be selectively adsorbed by the MIPs and the adsorbed isoniazid was sensed by its great enhancing effect on the weak CL reaction between luminol and periodate which were mixed in the flow cell.

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A molecularly imprinted polymer solid phase extraction (MISPE) method combined with flow-injection chemiluminescence (FI-CL) for the determination of residual tetracycline (TC) in fish samples is presented. The molecularly imprinted polymer (MIP) of TC was synthesized and particles of this MIP were packed into a polytetrafluoroethylene (PTFE) tube, which was connected into the sampling loop of an eight-way injection valve and served as the MISPE column for on-line selective adsorption of TC. The eluent (CH3CN : HNO3 (0.

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A method for detecting and identifying cationic surfactant in some chemical samples for daily use that include Head & Shoulder Ampoule and Slek Shower Lotion has been developed. In an acid medium, chromium(VI) oxidizes I(-) to produce I(2), I(2) binds excess of I(-) to form I(3)(-), and I(3)(-) can further react with a cationic surfactant (CS) (such as cetyldimethyl benzylammonium chloride (CDBAC), Zephiramine (Zeph), cetylpyridinium bromide (CPB), tetradecyl pyridinium bromide (TPB) and cetyltrimethylammonium bromide (CTAB)) to form ion-association complexes [CS][I(3)]. This results in a significant enhancement of resonance Rayleigh scattering (RRS) and appearance of new RRS spectra.

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Resonance Rayleigh-scattering method for the determination of proteins with gold nanoparticle probe.

Anal Biochem

June 2006

School of Chemistry and Chemical Engineering, Southwest China University, Beibei, Chongqing, People's Republic of China.

Gold nanoparticles with a 12-nm diameter were used as probes for the determination of proteins by resonance Rayleigh-scattering techniques. In weak acidic solution, large amounts of citrate anions will self-assemble on the surface of positively charged gold nanoparticles to form supermolecular compounds with negative charges. Below the isoelectric point, proteins with positive charges such as human serum albumin (HSA), bovine serum albumin (BSA), and ovalbumin (Ova) can bind gold nanoparticles to form larger volume products (the diameter of the binding product of gold nanoparticles with HSA is 23 nm.

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Radix Ranuncoli Ternati is clinically effective traditional Chinese medicine for multidrug resistant tuberculosis. Its active components and mechanism of action remain unsolved. Two dimensional gel electrophoresis (2-DE) was employed to address this problem.

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A novel flow injection chemiluminescence (CL) sensor for hydralazine determination using molecularly imprinted polymer (MIP) as recognition element is reported. Hydralazine-MIP was prepared through non-covalent copolymerization using methacrylic acid (MAA) monomer, hydralazine template and ethylene glycol dimethacrylate (EGDMA) cross-linker. Particles of the MIP were packed into a v-shape glass tube for on-line adsorption of the analyte of hydralazine.

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[Molecular mechanism of the integration and lysis of mycobacteriophage].

Wei Sheng Wu Xue Bao

October 2005

Institute of Modern Biopharmaceuticals, School of Life Sciences, Southwest China University, Chongqing.

Tuberculosis remains one of the major threats to public health. China is one of the heavy TB burden countries. Novel drugs and vaccines are urgently needed to combat the increasingly multidrug resistant TB.

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