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Ozonation of aromatic monomer compounds in water: factors determining reaction outcomes

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Frontiers of Environmental Science & Engineering 2023年第5期17卷 13-25页

作者： Zhe Wang Wenjuan Zhang Zhiwei Wang jing chang School of Environmental Science and Safety Engineering Tianjin University of TechnologyTianjin 300384China School of Environmental and Municipal Engineering Tianjin Key Laboratory of Aquatic Science and TechnologyTianjin Chengjian UniversityTianjin 300384China Tianjin Municipal Engineering Design&Research Institute Co. Ltd.Tianjin 300384China

For aromatic monomer compounds (AMCs), ozonation outcomes were usually predicted by the substituents of the benzene ring based on the electron inductive effect. However, the predicted results were occasionally unreliable for complex substituents, and other factors caused concern. In this study, p-chloronitrobenzene (p-CNB) and ibuprofen (IBP) were selected for ozonation. According to the electron inductive theory, p-CNB should be less oxidizable, but the opposite was true. The higher rates of p-CNB were due to various sources of assistance. First, the hydroxyl radical (•OH) contributed 90 % to p-CNB removal at pH 7.0, while its contribution to IBP removal was 50 %. Other contributions came from molecular O3 oxidation. Second, p-CNB achieved 40 % of the total organic carbon (TOC) removal and fewer by-product types and quantities, when compared to the results for IBP. Third, the oxidation of p-CNB started with hydroxyl substitution reactions on the benzene ring;then, the ring opened. However, IBP was initially oxidized mainly on the butane branched chain, with a chain-shortening process occurring before the ring opened. Finally, the degradation pathway of p-CNB was single and consumed fewer oxidants. However, both branches of IBP were attacked simultaneously, and three degradation pathways that relied on more oxidants were proposed. All of these factors were determinants of the rapid removal of p-CNB.

关键词： Ozonation Aromatic compound Oxidizing specie By-product Initial reaction position Degradation pathway

Joint Optimization Scheme Based on Beam Selection and Interference Cancellation in Lens Millimeter Wave NOMA Systems

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China Communications 2022年第4期19卷 57-66页

作者： Lei Xu jing Cai jing chang Hongyu Fang Xiaohui Li School of Electronics and Information Engineering Anhui UniversityHefei 230601China

Non-orthogonal multiple access(NOMA)has been integrated in millimeter-wave(mmWave)Massive MIMO systems to further enhance the spectrum efficiency, but NOMA has not been fully considered in lens mmWave systems. The fusion of these two technologies requires the joint design of beam selection and interference cancellation. In addition, when users follow the spatial cluster distribution, although the user clustering schemes based on K-means algorithm have been applied, the influence of the virtual and actual cluster center users on achievable sum rate has not been differentiated and analyzed in detail. To solve the above problems, a joint optimization scheme is proposed to maximize the achievable sum rate. The optimization problem is NP-hard, which is solved by using the divide-and-conquer approach. Concretely,based on the signal power loss analysis of directional deviation, a beam selection algorithm is designed for inter-cluster interference cancellation based on the Kmeans algorithm. Further for intra-cluster interference cancellation, a power allocation algorithm based on the bisection method is designed to guarantee the fairness of users in each cluster. The simulation results show that the proposed scheme offers a significant performance improvement in terms of both achievable sum rate and energy efficiency, and it is suitable for the large-scale user scenario due to its low complexity.

关键词： lens mmWave systems NOMA user clustering beam selection power allocation

Strong Skew Commutativity Preserving Maps on Rings with Involution

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Acta Mathematica Sinica,English Series 2016年第6期32卷 745-752页

作者： chang jing LI Quan Yuan CHEN School of Mathematical Sciences Shandong Normal University College of Information Jingdezhen Ceramic Institute

Let R be a unital ＊-ring with the unit I. Assume that R contains a symmetric idempotent P which satisfies ARP= 0 implies A = 0 and AR（I - P） = 0 implies A = 0. In this paper, it is shown that a surjective map Ф： R →R is strong skew commutativity preserving （that is, satisfies Ф（A）Ф（B） - Ф（B）Ф（A）＊： AB- BA＊ for all A, B ∈R） if and only if there exist a map f ： R → ZSz（R） and an element Z ∈ ZS（R） with Z^2 =I such that Ф（A） =ZA ＋ f（A） for all A ∈ R, where ZS（R） is the symmetric center of R. As applications, the strong skew commutativity preserving maps on unital prime ＊-rings and von Neumann algebras with no central summands of type I1 are characterized.

关键词： Strong skew commutativity preserving von Neumann algebras prime rings

Genetic Analysis of Carbon Isotope Discrimination and its Relation to Yield in a Wheat Doubled Haploid Population

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Journal of Integrative Plant Biology 2011年第9期53卷 719-730页

作者： Xianshan Wu Xiaoping chang Ruilian jing National Key Facility for Crop Gene Resources and Genetic Improvement Key Laboratory of Crop Germplasm and BiotechnologyMinistry of AgricultureInstitute of Crop ScienceChinese Academy of Agricultural SciencesHaidian DistrictBeijing 100081China

Carbon isotope discrimination（△13C） is considered a useful indicator for indirect selection of grain yield（GY） in ***,it is important to evaluate the genetic variation in △13C and its relationship with GY.A doubled haploid（DH） population derived from a cross of two common wheat varieties,Hanxuan 10（H10） and Lumai 14（L14）,was phenotyped for △13C in the flag leaf,GY and yield associated traits in two trials contrasted by water availability,specifically,rain-fed and *** trait loci（QTLs） were identified by single locus and two locus QTL *** for △13C were located on chromosomes 1A,2B,3B,5A,7A and 7B,and QTLs for other traits on all chromosomes except 1A,4D,5A,5B and *** population selected for high △13C had an increased frequency of QTL for high △13C,GY and number of spikes per plant（NSP） when grown under rain-fed conditions and only for high △13C and NSP when grown under irrigated conditions,which was consistent with agronomic performance of the corresponding trait values in the high △13C progeny;that is,significantly greater than that in the low △***,selection for △13C was beneficial in increasing grain yield in rain-fed environments.

关键词： carbon isotope discrimination drought stress QTL wheat yield.

Biological Properties of Chitosan Films with Different Degree of Deacetylation

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Journal of Materials Science & Technology 2008年第5期24卷 700-708页

作者： jing chang Wanshun LIU Baoqin HAN Bing LIU Department of Marine Life Science Ocean University of China Qingdao 266003 China

Chitin and chitosan films were prepared by solution casting method. Chitosan specimens used in this study were deacetylated by 50.4%, 69.2%, 85.5% and 96.3%. Their water content, protein adhesion ability, cytocompatibility, cell adhesion ability, in vitro and vivo degradability and biocompatibility were evaluated. Results indicated that with the degree of deacetylation （DD） between 50% and 70%, the chitosan showed higher water content. The higher the DD, the stronger protein adhesion ability the chitosan had. All the films have good cytocompatibility and the films with higher DD have better cell adhesion ability. Chitin films degraded more rapidly than others, which disappeared in 2 to 4 weeks after they were implanted in subcutaneous tissue and musculature. Their inflammatory reaction became weaker as the films degraded. As the DD got higher, the films degraded slower. The films of DD 85.5% and DD 90.3% even didn＇t disappeared in 12 weeks after they were implanted. Their inflammatory reaction was mild at the beginning of degradation, and became severe in 4 to 8 weeks, then weaken at last. This basic result can be very helpful for tissue engineering.

关键词： Chitosan Degree of deacetylation Biodegradability Cytocompatibility Celladhesion ability Biocompatibility

Absorption Cross Section of Static Einstein-Maxwell Dilation Axion Black Hole for Scalar Particles

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Communications in Theoretical Physics 2007年第4期47卷 665-668页

作者： LIU chang-Qing jing Ji-Liang Institute of Physics and Department of Physics Hunan Normal University Changsha 410081 China

The absorption cross section of the static Einstein-Maxwell dilaton axion （EMDA） black hole for scalar particles is investigated. It is shown that the ratio of the absorption cross section of the EMDA black hole to that of the Schwarzschild black hole decreases as the absolute value of the dilaton increases, and it becomes zero as the dilaton tends to its extremal value. It is also shown that the absorption cross section decreases as both the v and the absolute value of the dilaton increase, and it decreases as the mass of the particle decreases.

关键词： absorption cross section black hole dilaton

Properties and Structural Optimization of Pulverized Coal for Blast Furnace Injection

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Journal of Iron and Steel Research International 2011年第3期18卷 6-12页

作者： JIANG Hai-bing chang Jian LI jing School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The properties of mixed coals were studied on the basis of known various properties of the injecting coals in the *** structure of the injecting coals was optimized and put into practical *** was found that the ignition point was lowered with mixed coals,however,both combustibility and grindability were improved,and explosibility of the mixed coals were decreased as ***,mixed coals injection not only can improve the amount of the injecting coals greatly,but also improve the economical and technical indexes of the blast furnace.

关键词： blast furnace pulverized coal property injection

Adsorption and Thermal Decomposition of SiH4 on Cu(111) by Multiple-Scattering Cluster Method

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Chinese Physics Letters 2000年第7期17卷 525-527页

作者： HE Jiang-ping TANG jing-chang Department of Physics State Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhou 310027

Adsorption and thermal decomposition of SiH4 on Cu(111)at 110 K has been studied by the calculation of silicon K-edge near edge x-ray absorption fine structure spectra using multiple-scattering cluster *** is found th... 详细信息

关键词： method Cu(111) Adsorption

Near-Edge X-Ray Absorption Fine Structure Analyses of the Chain Model of Solid CS_(2)

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Chinese Physics Letters 1998年第3期15卷 203-204页

作者： XU Chun-yi TANG jing-chang Department of Physics State Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhou 310027

The S K-shell near-edge x-ray absorption fine structure spectra of solid CS_(2) have been calculated by means of the multiple-scattering cluster *** results show the existence of two kinds of absorption spectra which correspond to single-bond(C-S)and double-bond(C=S),respectively,and their superposition of the two spectra fits the experimental spectrum *** calculation supports the zigzag chain model of solid CS_(2) with C-C distance of 3.60±0.01Å.

关键词： method absorption spectra