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Synthesis, characterization and control of Proportion of Polymorph c in ITQ-16 and ITQ-17 Films

chemical Research in chinese Universities 2016年第6期32卷 895-901页

作者： cHEN Yanli FENG Lai College of Physics Optoelectronics and Enevgy Soochow University Suzhou 215006 P. R. China School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384 P. R. China

continuous ITQ-16 and ITQ-17 films on silicon wafer were prepared in fluoride media using TEAOH asorganic structure-directing agent. The proportion ofpolymorph c in the as-synthesized ITQ-16 and ITQ-17 films wasdetermined via X-ray diffraction characterization. The proportion of polymorph c in the ITQ-16 and 1TQ-17 filmswas controlled via optimizing the compositions of the reaction mixtures and reaction conditions, such as varyingthe Si/Ge molar ratio and adding n-propyl alcohol as a solvent in the reaction mixture, The Ge atoms in the reactionmedia strongly increased the crystallization of polymorph c in ITQ-16 and ITQ-17 films. Moreover, the stabilizingand buffering effect of n-propyl alcohol on crystal growth further enhanced the proportion of polymorph c in theITQ-16 and ITQ-17 films. For potential catalytic applications, A1 was incorporated into the framework ofpolymorphc, and a pure phase of polymorph c in Al-ITQ-17 film was achieved from the synthesis gel in the n-propyl alcohol phase.

关键词： Zeolite beta ITQ-16 ITQ-17 Polymorph c

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Sulfur-based mixotrophic denitrification with the stoichiometric S⁰/N ratio and methanol supplementation: effect of the c/N ratio on the process

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JOURNAL OF ENVIRONMENTAL ScIENcE AND HEALTH PART A-TOXIc/HAZARDOUS SUBSTANcES & ENVIRONMENTAL ENGINEERING 2021年第13期56卷 1420-1427页

作者： Yanez, Diana Guerrero, Lorna Borja, Rafael Huilinir, cesar Univ Santiago Chile Dept Ingn Quim Ave Libertador Bernardo OHiggins 3363 Santiago Chile Univ Tecn Federico Santa Maria Dept Ingn Quim & Ambiental Valparaiso Chile Inst Grasa CSIC Campus Univ Pablo de Olavide Seville Spain

The impact of the organic carbon to nitrate ratio (c/N ratio) on mixotrophic denitrification rate has been scarcely studied. Thus, this work aims to investigate the effect of the c/N ratio on the mixotrophic denitrification when methanol is used as a source of organic matter and elemental sulfur as an electron donor for autotrophic denitrification. For this, two initial concentrations of NO3--N (50 and 25 mg/L) at a stoichiometric ratio of S-0/N, and four initial c/N ratios (0, 0.6, 1.2, and 1.9 mg cH3OH/mg NO3- -N) were used at 25 (+/- 2) degrees c. The results showed that when using a c/N ratio of 0.6, the highest total nitrogen removal was obtained and the accumulation of nitrites was reduced, compared to an autotrophic system. The most significant contribution to nitrate consumption was through autotrophic denitrification (AuDeN) for a c/N ratio of 0.6 and 1.2, while for c/N = 1.9 the most significant contribution of nitrate consumption was through heterotrophic denitrification (HD). Finally, organic supplementation (methanol) served to increase the specific nitrate removal rate at high and low initial concentrations of substrate. Therefore, the best c/N ratio was 0.6 since it allowed for increasing the removal efficiency and the denitrification rate.

关键词： Mixotrophic denitrification c N ratio sulfur-based mixotrophic denitrification

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Size effect of carbon fiber-reinforced silicon carbide composites (c/c-Sic): Part 1-bending load and statistical effects

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JOURNAL OF THE EUROPEAN cERAMIc SOcIETY 2021年第14期41卷 6805-6814页

作者： Flauder, Stefan Langhof, Nico Krenkel, Walter Schaffoener, Stefan Univ Bayreuth Ceram Mat Engn CME Prof Rudiger Bormann Str 1 D-95447 Bayreuth Germany

This study analyzed the influence of the sample volume, number of tested specimen, and testing method on the flexural strength of fabric-reinforced ceramic matrix composites. For this purpose, seven different batches of c/cSic were prepared with four different sample thicknesses to determine the flexural strengths and Weibull moduli by three-and four-point flexural tests. The result showed that c/c-Sic exhibits a size effect of strength under bending load because a decrease of measured flexural strength with increased specimen size was observed. This size effect was discussed regarding the Weibull weakest link approach and the concept of quasi-brittle materials. The determined Weibull moduli were comparable for the same load condition but dissimilar for the identical material if the load condition were changed from three-to four-point bending. Hence, the Weibull modulus was found to be not an inherent material constant for c/c-Sic and the Weibull weakest link approach seems not appropriate.

关键词： ceramic matrix composites (cMc) Bending test Weibull statistics c c-Sic Size effect of strength

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Short stature explained by dimerization of human growth hormone induced by a p.c53S point mutation

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JOURNAL OF BIOLOGIcAL cHEMISTRY 2020年第15期295卷 4893-4901页

作者： Sander, Max Wu Zida Strasburger, christian J. Univ Med Berlin Dept Endocrinol Diabet & Nutr Med Campus Charite MitteCharitepl 1 D-10117 Berlin Germany

A homozygous mutation in growth hormone 1 (GH1) was recently identified in an individual with growth failure. This mutation, c.705G>c, causes replacement of cysteine at position 53 of the 191-amino-acid sequence of 22 kDa human GH (hGH) with serine (p.c53S). This hGH molecule (hereafter referred to as GH-c53S) lacks the disulfide bond between ***-53 and ***-165, which is highly conserved among species. It has been reported previously that monomeric GH-c53S has reduced bioactivity compared with WT GH (GH-WT) because of its decreased ability to bind and activate the GH receptor in vitro. In this study, we discovered that substitution of ***-53 in hGH significantly increased formation of hGH dimers in pituitary cells. We expressed His-tagged hGH variants in the cytoplasm of genetically modified Rosetta-gami B DE3 Escherichia coli cells, facilitating high-yield production. We observed that the bioactivity of monomeric GH-c53S is 25.2% of that of GH-WT and that dimeric GH-c53S?His has no significant bioactivity in cell proliferation assays. We also found that the expression of GH-c53S in pituitary cells deviates from that of GH-WT. GH-c53S was exclusively stained in the Golgi apparatus, and no secretory granules formed for this variant, impairing its stimulated release. In summary, the unpaired cys-165 in GH-c53S forms a disulfide bond linking two hGH molecules in pituitary cells. We conclude that the GH-c53S dimer is inactive and responsible for the growth failure in the affected individual.

关键词： growth hormone disulfide dimerization pituitary gland protein folding c 705G>c cysteine GH-c53S growth hormone deficiency

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Submodules of the groupoid c~*-algebra

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Science china Mathematics 1998年第4期41卷 379-385页

作者：严绍宗陈晓漫徐胜芝 1. Institute of Mathematics Fudan University 200433 Shanghai China

Given an r-discrete, principal and amenable groupoid, the bijective correspondence between the family c the closedc o(G 0)-bimodules ofc(G) and the family of the open subsets of the groupoidG is established. More over... 详细信息

关键词： groupoid c algebra G set bimodule rigidity

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THE INHIBITION OF PHOTOcHEMIcAL SMOG .9. MODEL-cALcULATIONS OF THE EFFEcT OF (c2H5)2NOH ON c2H4-NOX ATMOSPHERES

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ATMOSPHERIc ENVIRONMENT 1985年第4期19卷 597-605页

作者： HEIcKLEN, J PENN STATE UNIV CTR AIR ENVIRONM STUDIES UNIVERSITY PK PA 16802 USA

computer modeling of c2H4-NOx atmospheres with and without (c2H5)2NOH present were performed. The reaction scheme consists of 102 reactions and 45 reaction species plus N2, which is unreactive. No perceptible reaction occurs unless HNO2 is present, which can photodecompose to give HO radicals. HNO2 is produced from the reaction of H2O, NO and NO2. The equilibrium apparently is rapidly maintained through heterogeneous reactions. For systems with no H2O present, an artificial HO-source term must be included. A number of calculations for c2H4-NOx systems were made for conditions of various dilution factors, (c2H5)2NOH concentrations and feed rates, and various initial [NO]/[NO2] ratios. If NO2 is present initially it can photodecompose in air to produce a low level of O3 which in turn reacts with (c2H5)2NOH to give HO radicals. This can accelerate the onset of ultimate O3 formation. However, if sufficient (c2H5)2NOH is present or it is added before NO2 is produced, it delays O3 production. Under real atmospheric conditions which include dilution and diurnal variation in the sun''s intensity, 2nd-day effects are not important.

关键词： Photochemical smog diethylhydroxylamine model calculations environment modification c 2 H 4 -NO x atmospheres

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Three-dimensional micro-pipelines high thermal conductive c/Sic composites

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cERAMIcS INTERNATIONAL 2021年第24期47卷 34333-34340页

作者： Zhang, Yunhai Liu, Yongsheng cao, Liyang Fang, Hui Liu, Bin cao, Yejie Wang, Jing chen, Jian Pan, Yu Northwestern Polytech Univ Sci & Technol Thermostruct Composite Mat Lab Xian 710072 Shaanxi Peoples R China Northwestern Polytech Univ Sch Aeronaut Xian 710072 Shaanxi Peoples R China Acad Mil Sci PLA China Natl Innovat Inst Def Technol Beijing 100071 Peoples R China Natl Univ Def Technol Coll Aerosp Sci & Engn Sci & Technol Scramjet Lab Changsha 410073 Hunan Peoples R China

carbon/silicon carbide (c/Sic) composites are usually regarded as thermal protective system materials and widely applied in hypersonic vehicles or ramjet. However, poor thermal conductivity of c/Sic composites, leading to severe heat concentration and thermal stress during the high-speed operation of hypersonic vehicle, limits their broad-range of practical applications. Modification with high thermal conductive fillers is an optional method;however, controllable dispersion and orientation of the fillers to construct continuous and ordered heat conductive channel has been proven to be a challenging task. Herein, based on high thermal conductivity fibers, a three-dimensional micro-pipeline preform was developed for the preparation of structure-function integrated c/Sic composites. The technical feasibility of the method, the characteristics of microstructures, and the thermal conductivity and bending strength of the as-obtained composites were systematically studied. Results revealed that the thermal conductivities of as-obtained composites reached 150.2 and 46.7 W m-1 K-1 for in-plane and out-of-plane direction, respectively. The bending strength obtained herein is 264.4 MPa, which is lower than that of polyacrylonitrile c/Sic composites. However, the fine control over the component and microstructure or densification could provide a higher value in the future research. In sum, the proposed method provides a convenient and feasible approach to prepare high thermal conductive c/Sic composites.

关键词： c Sic composites Micro-pipelines Thermal conductivity Bending strength Heat conductive channels

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Simultaneous nitrogen and carbon removal in a packed A/O reactor: effect of c/N ratio on microbial community structure

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BIOPROcESS AND BIOSYSTEMS ENGINEERING 2020年第7期43卷 1241-1252页

作者： Ding, Shuai He, Jian Luo, Xingzhang Zheng, Zheng Fudan Univ Dept Environm Sci & Engn Room 2026Environm Bldg2005 Songhu Rd Shanghai 200433 Peoples R China

In this research, a novel packed anoxic/oxic moving bed biofilm reactor (MBBR) was established to achieve high-organic matter removal rates, despite the carbon/nitrogen (c/N) ratio of 2.7-5.1 in the influent. Simultaneous nitrification-denitrification (SND) was investigated under a long sludge retention time of 104 days. The system exhibited excellent performance in pollutant removal, with chemical oxygen demand and total nitrogen (TN) enhanced to 93.6-97.4% and 34.4-60%, respectively. Under low c/N conditions, the nitrogen removal process of A/O MBBR system was mainly achieved by anaerobic denitrification. The increase of c/N ratio enhanced SND rate of the aerobic section, where dissolved oxygen was maintained at the range of 4-6 mg/L, and resulted in higher TN removal efficiency. The microbial composition and structures were analyzed utilizing the MiSeq Illumina sequencing technique. High-throughput pyrosequencing results indicated that the dominant microorganisms were Proteobacteria and Bacteroidetes at the phylum level, which contributes to the removal of organics matters. In the aerobic section, abundances of Nitrospirae (1.12-29.33%), Burkholderiales (2.15-21.38%), and Sphingobacteriales (2.92-11.67%) rose with increasing c/N ratio in the influent, this proved that SND did occur in the aerobic zone. As the c/N ratio of influent increased, the SND phenomenon in the aerobic zone of the system is the main mechanism for greatly improving the removal rate of TN in the aerobic section. The c/N ratio in the aerobic zone is not required to be high to exhibit good TN removal performance. When c/NH4+ and c/TN in the aerobic zone were higher than 2.29 and 1.77, respectively, TN removal efficiency was higher than 60%, which means that carbon sources added to the reactor could be saved. This study would be vital for a better understanding of microbial structures within a packed A/O MBBR and the development of cost-efficient strategies for the treatment of low c/N wastewate

关键词： Packed A O reactor Moving bed biofilm reactor c N ratio Simultaneous nitrification-denitrification (SND) Microbial community structure

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Preparation of high performance LiFePO4/c by extracting iron element from iron tailings by concentrated sulfuric acid hot dip method

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IONIcS 2020年第4期26卷 1645-1655页

作者： Wang, Yingling Wang, Yafeng Luo, Shaohua Liu, chengjun Teng, Fei chen, Huanhuan Shen, Huiliang Gao, Desheng Northeastern Univ Sch Met Shenyang 110819 Peoples R China Northeastern Univ Minist Educ Key Lab Ecol Met Multimetall Ores Shenyang 110819 Peoples R China Northeastern Univ Qinhuangdao Sch Resources & Mat Qinhuangdao 066004 Hebei Peoples R China Northeastern Univ Sch Mat Sci & Engn Shenyang 110819 Peoples R China

LiFePO4/c cathode materials are synthesized by carbothermal reduction process using FePO4 as iron and phosphorus source, and starch as carbon source. The FePO4 precursor was prepared by leaching iron tailings with concentrated sulfuric acid and then leaching with phosphoric acid and hydrogen peroxide. The morphology and structure of FePO4 precursors prepared under different pH conditions were studied by using thermogravimetric-differential analysis (TG-DTA), infrared analysis (FTIR), x-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The effect of the FePO4 material on the properties of the synthesized LiFePO4 cathode was investigated by charge and discharge cycles. On this basis, the effects of different molar ratios of c and LiFePO4 on the performance of synthetic product LiFePO4/c were studied using starch as carbon source. The results show that the FePO4 precursor prepared under the condition of pH 2 is the raw material, and the LiFePO4/c cathode material synthesized by adding 45% carbon has the best performance. The first cycle discharge capacity reached 142.6 mAh g(-1) at a current density of 0.1 degrees c, reaching 83.9% of its theoretical capacity. This work proposes a novel and effective method to utilize the iron tailings.

关键词： cathode material LiFePO4 c Iron tailings concentrated sulfuric acid leaching FePO4 precursor

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Ordered Element Distributed c3N Quantum Dots Manipulated crystallization Kinetics for 2D csPbI3 Solar cells with Ultra-High Performance

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SMALL 2022年第15期18卷 2108090-2108090页

作者： Li, Zhizai Yang, Siwei Ye, caichao Wang, Gang Ma, Bo Yao, Huanhuan Wang, Qian Peng, Guoqiang Wang, Qiang Zhang, Hao-Li Jin, Zhiwen Lanzhou Univ Sch Phys Sci & Technol Lanzhou 730000 Peoples R China Lanzhou Univ Key Lab Magnetism & Magnet Mat MoE Lanzhou 730000 Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol State Key Lab Funct Mat Informat Lab Graphene Mat & Applicat Shanghai 200050 Peoples R China Univ Chinese Acad Sci Coll Mat Sci & Optoelect Technol Beijing Peoples R China Southern Univ Sci & Technol Acad Adv Interdisciplinary Studies Shenzhen 518055 Guangdong Peoples R China Southern Univ Sci & Technol Guangdong Prov Key Lab Computat Sci & Mat Design Shenzhen 518055 Guangdong Peoples R China Ningbo Univ Sch Phys Sci & Technol Dept Microelect Sci & Engn Ningbo 315211 Peoples R China Lanzhou Univ State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China Lanzhou Univ Key Lab Special Funct Mat & Struct Design Lanzhou 730000 Peoples R China Lanzhou Univ Coll Chem & Chem Engn Lanzhou 730000 Peoples R China

Two-dimensional (2D) csPbI3 is developed to conquer the phase-stability problem of csPbI3 by introducing bulky organic cations to produce a steric hindrance effect. However, organic cations also inevitably increase the formation energy and difficulty in crystallization kinetics regulation. Such poor crystallization process modulation of 2D csPbI3 leads to disordered phase-arrangement, which impedes the transport of photo-generated carriers and worsens device performance. Herein, a type of c3N quantum dots (QDs) with ordered carbon and nitrogen atoms to manipulate the crystallization process of 2D csPbI3 for improving the crystallization pathway, phase-arrangement and morphology, is introduced. combination analyses of theoretical simulation, morphology regulation and femtosecond transient absorption (fs-TA) characterization, show that the c3N QDs induce the formation of electron-rich regions to adsorb bulky organic cations and provide nucleation sites to realize a bi-directional crystallization process. Meanwhile, the quality of 2D csPbI3 film is improved with lower trap density, higher surface potential, and compact morphology. As a result, the power conversion efficiency (PcE) of the optimized device (n = 5) boosts to an ultra-high value of 15.63% with strengthened environmental stability. Moreover, the simple c3N QDs insertion method shows good universality to other bulky organic cations of Ruddlesden-Popper and Dion-Jacobson, providing a good modulation strategy for other optoelectronic devices.

关键词： 2D csPbI (3) c N-3 crystallization kinetics phase management

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