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Decentralized wastewater treatment technologies and management in Chinese villages

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 929-936页

作者： Xuesong GUO Zehang LIU Meixue CHEN Junxin LIU Min YANG state key laboratory of Environmental Aquatic chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Problems treating sewage in rural areas in China have attracted increasing attention in recent years. However, only 6% of rural areas had spray drainage and wastewater treatment systems by the end of 2010. It is necessary to assess the technologies currently used so that sewage treatment in rural areas can be developed appropriately, to provide reliable and affordable waste- water treatment, in these areas. We evaluated the sewage treatment technologies currently used in rural areas by conducting case studies on 62 facilities that had each been operating for at least one year. Our study was carried out between 2009 and 2011, and the aim was to assess the situation during that period and assess any problems involved in decentralized sewage treatment in villages. We found that decentralized sewage treatment is the most popular wastewater treatment method in villages, and that the most common primary treatment technology used in rural areas is the septic tank. Our investigation highlights the need to establish standards for assessing effluent quality, including a range of target pollutants. Our results also show that effluents should be reused to meet the local environmental requirements in different areas, especially in ecologically sensitive areas.

关键词： decentralized treatment strategy sustainable development village wastewater treatment situation

Synthesis and Enhanced Photocatalytic Activity of Regularly Shaped Cu2O Nanowire Polyhedra

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Nano Research 2011年第5期4卷 448-459页

作者： Jing Shi Jin LI Xiaojian Huang Yiwei Tan state key laboratory of Materials-Oriented Chemical Engineering School of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

A series of unique nanowire superstructures, Cu2O nanowire polyhedra, have been synthesized through a cost-effective hydrothermal route. Three types of nanowire polyhedra, namely octahedra, concave octahedra, and hexapods, were formed in high morphological yields （90%） by reducing cupric acetate with o-anisidine or o-phenetidine in the presence of carboxylic acids. The architectures of these Cu2O nanowire polyhedra were examined by electron microscopy, which revealed ordered, highly aligned CU2O nanowires within the polyhedral outlines. The growth of the Cu2O nanowire polyhedra is controlled by the orientation and growth rates of the nanowire branches which are adjusted by addition of carboxylic acids. Compared to the Cu2O samples reported in the recent literature, the Cu2O nanowire octahedra exhibit notably enhanced photocatalytic activities for dye degradation in the presence of H202 under visible light, probably due to the high-density charge carriers photoexcited from the branched nanowires with their special structures. Additionally, the discussion in the recent literature of the photocatalytic activity of Cu2O in the absence of H2O2 for direct photodegradation of dyes seems questionable.

关键词： Nanowire superstructures polyhedra cuprous oxide photocatalysis morphology control

On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan Cui Peng Chen Peng‑Fei Wang Xiao‑Wu Li Department of Materials Physics and chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China state key laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

A Comparison Analysis of Chemical Composition of Aerosols in the Dust and Non-Dust Periods in Beijing

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Advances in Atmospheric Sciences 2004年第2期21卷 300-305页

作者：张仁健徐永福韩志伟 state key laboratory of Atmospheric Boundary Layer Physics and Atmospheric chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029

Dust events occurred frequently in Beijing in recent years. In this work, 120 aerosol samples were collected in two typical dust events (21-22 March and 15 May) and a non-dust period in Beijing from March to May 2001. Samples were analyzed for major elemental components by the Proton Induced X-ray Emission (PIXE) method. Results show that the enrichment factors of crustal elements such as Mg, Al, and Ti had little differences between the dust period and the non-dust period in Beijing, while the enrichment factors of other elements that have a relation to anthropogenic emissions were very low during the dust period. The results derived by using multivariate factor analysis from the observation data show that the sources such as soil dust, industry, and fuel combustion were among the major contributors to the particles in Beijing.

关键词： dust aerosol chemical composition Proton Induced X-ray Emission method

Electrostatic and hydrophobic interaction cooperative nanochaperone regulates protein folding

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Aggregate

Aggregate 2024年第1期5卷 419-426页

作者： Xiaohui Wu Fei Deng Yujie Chen Mengchen Xu Feihe Ma Linqi Shi key laboratory of Functional Polymer Materials of Ministry of Education State Key Laboratory of Medicinal Chemical BiologyInstitute of Polymer Chemistry and College of ChemistryNankai UniversityTianjinP.R.China School of Materials Science and Engineering and state key laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjinP.R.China

Natural molecular chaperones utilize spatially ordered multiple molecular forces to effectively regulate protein ***,synthesis of such molecules is a big *** concept of“aggregate science”provides insights to construct chemical entities(aggregates)beyond molecular levels to mimic both the structure and function of natural *** by this concept,herein we fabricate a novel multi-interaction(i.e.,electrostatic and hydrophobic interaction)cooperative nanochaperone(multi-co-nChap)to regulating protein *** multi-co-nChap is fabricated by rationally introducing electrostatic interactions to the surface(corona)and confined hydrophobic microdomains(shell)of traditional single-hydrophobic interaction *** demonstrate that the corona electrostatic attraction facilitates the diffusion of clients into the hydrophobic microdomains,while the shell electrostatic interaction balances the capture and release of *** finely synergizing corona electrostatic attraction with shell electrostatic repulsion and hydrophobic interaction,the optimized multi-co-nChap effectively facilitated de novo folding of nascent ***,the synergy between corona electrostatic attraction,shell electrostatic attraction and shell hydrophobic interaction significantly enhanced the capability of multi-co-nChap to protect native proteins from denaturation at harsh *** work provides important insights for understanding and design of nanochaperone,which is a kind of ordered aggregate with chaperone-like activity that beyond the level of single molecule.

关键词： chaperone-like activity cooperative effect nanochaperones ordered aggregates protein folding

Synthesis and Crystal Structure of a 2D Cu Framework Constructed from Dinuclear Building Units

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Chinese Journal of Structural chemistry 2014年第12期33卷 1807-1812页

作者：陈惠马成丙陈昌能 state key laboratory of Structural chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences

A novel 2D Cu coordination polymer [Cu4(pca)4(H2O)2(DMSO)2·2DMSO·2H2O]n(2, H2 pca = pyrazole-3-carboxylic acid) has been prepared by dissolving a dinuclear Cu complex Cu2(py)3(pca)2(H2O)·(H2O)(1) in DMSO solution and structurally characterized by X-ray diffraction. The polymer crystallizes in space group P1 with a = 9.538(3), b = 9.714(3), c = 10.765(3) A, α = 86.492(6), β = 84.007(7), γ = 82.592(6)o, Mr = 1079.04, V = 982.4(5) A3, Z = 1, Dc = 1.824 g/cm3, μ = 2.425 mm-1 and F(000) = 548. The final refinement gave R = 0.0785 and w R = 0.1940 for 2787 reflections with I > 2σ(I). The structure of 2 consists of Cu4(pca)4(H2O)2(DMSO)2·2DMSO·2H2O units, which can be viewed as two dinuclear subunits of Cu2(pca)2(H2O)2 and Cu2(pca)2(DMSO)2 connected to each other alternately, with solvent DMSO and H2 O molecules around. The framework features a grid-like topology, with the walls of the grids composed of Cu4(pca)4 units, and the coordinated solvent molecules trapped in the grids.

关键词： copper coordination polymer crystal structure building block

Fast Determination of Phenanthrene in Soil by Gas Chroma- tography-Mass Spectrometry Using Chemometric Resolution and Standard Addition Method

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Chinese Journal of chemistry 2013年第4期31卷 545-550页

作者： Weiwei Yu Wensheng Cai Xueguang Shao state key laboratory of Medicinal Chemical Biology Research Center for Analytical Sciences College of Chemistry Nankai University Tianjin 300071 China

A method for fast determination of the component in complex samples by using gas chromatography-mass spectrometry （GC-MS） was developed and used for quantitative analysis of phenanthrene in soils. In the method, window independent component analysis （WICA） was used for resolving the mass spectrum and non-negative im- mune algorithm （NNIA） was employed for obtaining the chromatographic profile. Therefore, spectral and chroma- tographic information of a specific component can be obtained from the measured GC-MS data of overlapping and high background. Six soil samples collected from different places were analyzed. The tedious pretreatments in pre- paring the samples and the elution in the separation were simplified for speeding up the analysis. Due to the com- plexity of the matrix, standard addition method was adopted for the final quantification. The applicability of the method was validated with a spiked sample and the results of the six samples are reasonable.

关键词： phenanthrene gas chromatography-mass spectrometry standard addition method chemoinformatics immune algorithm

Syntheses and Crystal Structures of Two Trinuclear Iron(Ⅲ) Carboxylate Complexes: Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl· 3H 2O and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl(Py=pyridine) ①

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Chinese Journal of Structural chemistry 1999年第1期18卷 53-58页

作者： CUI Yong WANG Yan-Ming ZHENG Yu ZHOU Wen-Bo HE Ling-Jie CAI Shu-Hua CHEN Bo ZHANG Lin-Na Fujian Institute of Research on the Structure of Matter State Key Laboratory of Structural Chemistry the Chinese Academy of Sciences Fuzhou Fujian 350002 China

Two new oxo centered trinuclear iron complexes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl·3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl 2 were prepared in non aqueous solvent and thei... 详细信息

Two new oxo centered trinuclear iron complexes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl·3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl 2 were prepared in non aqueous solvent and their crystal structures have been determined. Crystal 1 is monoclinic, space group P2 1/n, a=9.909(3), b=24.467(8), c=14.542(7) , β=107.85(4)° V=3356(4)  3, Z=4, M r=765.52, D c =1.52 g/cm 3, μ= 14.28 cm -1 , F(000) =1588 and R=0.059, R w =0.071 for 3745 unique reflections with I>3σ(I) . Crystal 2 belongs to the monoclinic system with space group C2/c, a=13.750(3), b=18.439(4), c=16.696(3) , β=93.42(3)°, V=4226(3)  3, Z=4, M r=894.73, D c =1.41 g/cm 3, μ =11.4 cm -1, F (000)=2322 and R=0.058, R w =0 062 for 2272 unique reflections with I>3σ(I). The two structures contain the same trimetal framework in which three iron(Ⅲ) atoms form a nearly equilateral triangle with a μ 3 oxygen atom in the centre.

关键词： syntheses crystal structures carboxylate complexes iron complexes

Copper-Catalyzed Ring-Opening/Borylation of Cyclopropenes

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CCS chemistry 2022年第4期4卷 1232-1237页

作者： Ming-Yao Huang Yu-Tao Zhao Hao Chai Cheng-Da Zhang Shou-Fei Zhu The state key laboratory and Institute of Elemento-Organic chemistry College of ChemistryNankai UniversityTianjin 300071

Since organoboron compounds readily undergo a diverse array of transformations and are widely used in various fields,the development of C-B-bondforming reactions have attracted considerable ***,we report a new method for forming C-B bonds by means of Cu-catalyzed ring-opening/borylation reactions of *** method provides efficient access to a new type of stable allylborane-Lewis base adduct,which is a versatile *** configuration of the products can be well controlled with this method,and some of the configurations we obtained are inaccessible by other catalytic methods for generating *** studies indicated that the reactions proceed via insertion of an alkenyl Cu carbene—generated in situ by cyclopropene ring opening—into the B-H bond;the ring-opening step determines both the rate and stereochemistry.

关键词： cyclopropenes carbenes B-H bond insertion copper catalysis allylboranes