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Inactivation, reactivation and regrowth of indigenous bacteria in reclaimed water after chlorine disinfection of a municipal wastewater treatment plant

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Journal of Environmental Sciences 2013年第7期25卷 1319-1325页

作者： Dan Li Siyu zeng April z. Gu Miao He Hanchang shi Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University Department of Civil and Environmental Engineering Northeastern University

Disinfection of reclaimed water prior to reuse is important to prevent the transmission of pathogens. Chlorine is a widely utilized disinfectant and as such is a leading contender for disinfection of reclaimed water. To understand the risks of chlorination resulting from the potential selection of pathogenic bacteria, the inactivation, reactivation and regrowth rates of indigenous bacteria were investigated in reclaimed water after chlorine disinfection. Inactivation of total coliforms, Enterococcus and Salmonella showed linear correlations, with constants of 0.1384, 0.1624 and 0.057 L/（mg·min） and R 2 of 0.7617, 0.8316 and 0.845, respectively. However, inactivation of total viable cells by measurement of metabolic activity typically showed a linear correlation at lower chlorine dose （0-22 （mg·min）/L）, and a trailing region with chlorine dose increasing from 22 to 69 （mg·min）/L. Reactivation and regrowth of bacteria were most likely to occur after exposure to lower chlorine doses, and extents of reactivation decreased gradually with increasing chlorine dose. In contrast to total coliforms and Enterococcus, Salmonella had a high level of regrowth and reactivation, and still had 2% regrowth even after chlorination of 69 （mg·min）/L and 24 hr storage. The bacterial compositions were also significantly altered by chlorination and storage of reclaimed water, and the ratio of Salmonella was significantly increased from 0.001% to 0.045% after chlorination of 69 （mg·min）/L and 24 hr storage. These trends indicated that chlorination contributes to the selection of chlorine-resistant pathogenic bacteria, and regrowth of pathogenic bacteria after chlorination in reclaimed water with a long retention time could threaten public health security during wastewater reuse.

关键词： inactivation regrowth reactivation indigenous bacteria reclaimed water

Atomically dispersed calcium as solid strong base catalyst with high activity and stability

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Green Energy & Environment 2024年第10期9卷 1619-1626页

作者： Xiang-Bin Shao zhi-Wei Xing Si-Yu Liu Ke-Xin Miao shi-Chao Qi Song-Song Peng Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu Road

Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental ***,their widespread applications are impeded by basic components aggregation and low *** this work,we fabricate single calcium atoms on graphene （denoted as Ca1/G） by use of a redox strategy for the first time,producing solid strong base catalyst with high activity and *** precursor Ca（NO3）2is first reduced to CaO at 400℃ by the support graphene,forming CaO/G with conventional basic sites,and the subsequent reduction at 850℃ results in the generation of Ca1/G with atomically dispersed *** characterizations reveal that Ca single atoms are anchored on graphene in tetra-coordination （Ca–C2–N2） where N is in situ doped from Ca（NO3）*** atomically dispersed Ca,along with their anchoring on the support,endow Ca1/G with high activity and stability toward the transesterification reaction of ethylene carbonate with *** turnover frequency value reaches 128.0 h-1on Ca1/G,which is much higher than the traditional counterpart CaO/G and various reported solid strong bases (2.9–46.2 h-1).Moreover,the activity of Ca1/G is well maintained during 5 cycles,while 60% of activity is lost for the conventional analogue CaO/G due to the leaching of Ca.

关键词： Solid strong base Single Ca atoms Heterogeneous catalysts Transesterification Reaction

On a general theory for compressing process and aeroacoustics:linear analysis

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Acta Mechanica Sinica 2010年第3期26卷 355-364页

作者： E .Mao Y. P. shi J. z. Wu State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University 100871 Beijing China University of Tennessee Space Institute Tullahoma TN 37388 USA

Of the three mutually coupled fundamental processes （shearing, compressing, and thermal） in a general fluid motion, only the general formulation for the compress- ing process and a subprocess of it, the subject of aeroacous- tics, as well as their physical coupling with shearing and thermal processes, have so far not reached a consensus. This situation has caused difficulties for various in-depth complex multiprocess flow diagnosis, optimal configuration design, and flow/noise control. As the first step toward the desired formulation in fully nonlinear regime, this paper employs the operator factorization method to revisit the analytic linear theories of the fundamental processes and their decomposi- tion, especially the further splitting of compressing process into acoustic and entropy modes, developed in 1940s-1980s. The flow treated here is small disturbances of a compressible, viscous, and heat-conducting polytropic gas in an unbounded domain with arbitrary source of mass, external body force, and heat addition. Previous results are thereby revised and extended to a complete and unified theory. The theory pro- vides a necessary basis and valuable guidance for developing corresponding nonlinear theory by clarifying certain basic issues, such as the proper choice of characteristic variables of compressing process and the feature of their governing equations.

关键词： Longitudinal (compressing) processTransversal (shearing) process Acoustic mode Entropy mode Aeroacoustics

Research Progress in the Fabrication of Covalent Organic Framework Membranes for Chemical Separations

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Chinese Journal of Polymer Science 2024年第2期42卷 141-158,I0005页

作者： Cui-Ting Ding Jin-Qiu Yuan Meng-Ying Xie Qing-Yuan Liu zeng-Guang Yao shi-Yu zhang Run-Nan zhang Hong Wu zhong-Yi Jiang Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China zhejiang Institute of Tianjin University NingboZhejiang315201China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Tianjin Key Laboratory of Membrane Science and Desalination Technology Tianjin UniversityTianjin300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.

关键词： Covalent organic frameworks Covalent organic framework membranes Water treatment Organic solvent nanofiltration Gas separation

Design and optimization of piperidinesubstituted thiophene[3,2-d]pyrimidine-based HIV-1 NNRTIs with improved drug resistance and pharmacokinetic profiles

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Acta Pharmaceutica Sinica B 2024年第7期14卷 3110-3124页

作者： Yanying Sun zhenzhen zhou zhongling shi Fabao zhao Minghui Xie zongji zhuo Erik De Clercq Christophe Pannecouqueb Dongwei Kang Peng zhan Xinyong Liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesShandong UniversityJinan 250012China Rega Institute for Medical Research Laboratory of Virology and ChemotherapyK.U.LeuvenLeuven B-3000Belgium China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province Jinan 250012China

HIV-1 reverse transcriptase(RT)has received great attention as an attractive therapeutic target for acquired immune deficiency syndrome(AIDS),but the inevitable drug resistance and side effects have always been major challenges faced by non-nucleoside reverse transcriptase inhibitors(NNRTIs).This work aimed to identify novel chemotypes of anti-HIV-1 agents with improved drugresistance profiles,reduced toxicity,and excellent druggability.A series of diarylpyrimidine(DAPY)derivatives were prepared via structural modifications of the leads K-5a2 and *** them,15a with dimethylphosphine oxide moiety showed the most prominent antiviral potency against all of the tested viral panel,being 1.6-fold(WT,EC_(50) z 1.75 nmol/L),3.0-fold(L100I,EC_(50) z 2.84 nmol/L),2.4-fold(K103N,EC_(50) z 1.27 nmol/L),3.3-fold(Y181C,EC50 z 5.38 nmol/L),2.9-fold(Y188L,EC_(50) z 7.96 nmol/L),2.5-fold(E138K,EC_(50) z 4.28 nmol/L),4.8-fold(F227L/V106A,EC_(50) z 3.76 nmol/L)and 5.3-fold(RES056,EC_(50) z 15.8 nmol/L)more effective than that of the marketed drug *** docking results illustrated the detailed interactions formed by compound 15a and WT,F227L/V106A,and RES056 ***,15a-HCl carried outstanding pharmacokinetic(t1/2 z 1.32 h,F z 40.8%)and safety profiles(LD_(50)>2000 mg/kg),which demonstrated that 15a HCl is a potential anti-HIV-1 drug candidate.

关键词： HIV-1 NNRTIs NNIBP Structural alert Anti-HIV-1 drug candidate

Deep Learning Quantum States for Hamiltonian Estimation

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Chinese Physics Letters 2021年第11期38卷 1-6页

作者： Xinran Ma z.C.Tu shi-Ju Ran Department of Physics Beijing Normal UniversityBeijing 100875China Department of Physics Capital Normal UniversityBeijing 100048China

Human experts cannot efficiently access physical information of a quantum many-body states by simply "reading"its coefficients, but have to reply on the previous knowledge such as order parameters and quantum *** demonstrate that convolutional neural network(CNN) can learn from coefficients of many-body states or reduced density matrices to estimate the physical parameters of the interacting Hamiltonians, such as coupling strengths and magnetic fields, provided the states as the ground states. We propose QubismNet that consists of two main parts: the Qubism map that visualizes the ground states(or the purified reduced density matrices) as images, and a CNN that maps the images to the target physical parameters. By assuming certain constraints on the training set for the sake of balance, QubismNet exhibits impressive powers of learning and generalization on several quantum spin models. While the training samples are restricted to the states from certain ranges of the parameters, QubismNet can accurately estimate the parameters of the states beyond such training regions. For instance, our results show that QubismNet can estimate the magnetic fields near the critical point by learning from the states away from the critical vicinity. Our work provides a data-driven way to infer the Hamiltonians that give the designed ground states, and therefore would benefit the existing and future generations of quantum technologies such as Hamiltonian-based quantum simulations and state tomography.

关键词： CNN MSE RDM image Hamiltonian Deep Learning Quantum States for Hamiltonian Estimation Quantum

Natural product-induced oxidative stress-synergistic anti-tumor effects of chemotherapeutic agents

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Traditional Medicine Research 2024年第3期9卷 10-23页

作者： Shu-Fan Wang shi-Qi Dong Quan Dong Wen-Xin Lin Mei Dong Duo Liu Department of Pharmacy Harbin Medical University Cancer HospitalHarbin 150086China

Reactive oxygen species are closely related to tumor *** recent years,reactive oxygen species has become a hot spot in tumor therapy,and many natural substances in nature contain compound components with anti-tumor ***,there is a lack of discussion on the synergistic anti-tumor effects of natural products in combination with chemotherapeutic drugs through reactive oxygen *** terms“natural products”,“reactive oxygen species”,“anti-tumor”,and“chemotherapy”were used to identify the synergistic effects of natural *** conducted a systematic literature search in PubMed and Web of Science databases for relevant research articles and reviews published in recent *** systematically summarized the studies related to anti-tumor active ingredients in natural compounds in the field of reactive oxygen species in recent years.A total of 77 relevant literatures were *** them,45 literatures containing various natural products such as terpenoids,flavonoids,alkaloids,*** anti-tumor effects by regulating reactive oxygen species levels,and 32 literatures regarding adjunctive role of natural products in anti-tumor *** this study,we found that natural products exert anti-tumor effects by elevating reactive oxygen species *** provides strong theoretical support for future clinical studies.

关键词： nature products tumor reactive oxygen species combination chemotherapy oxidative stress

RESEARCH ON LASER DIRECT DEPOSITION PROCESS OF Ti-6Al-4V ALLOY

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 171-180页

作者： S.Y. Gao Y.z. zhang L.K. shi B.L. Du M.z. Xi H.z. Ji Mechanical Engineering College Yanshan University O~mhuangdao 066004 China Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Laser direct deposition （LDD） of metallic components is an advanced technology of combining CAD/CAM （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the LDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by LDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the LDD process. Because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

Organoid intelligence:Integration of organoid technology and artificial intelligence in the new era of in vitro models

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Medicine in Novel Technology and Devices 2024年第1期21卷 39-44页

作者： Huaiyu shi Andrew Kowalczewski Danny Vu Xiyuan Liu Asif Salekin Huaxiao Yang zhen Ma Department of Biomedical&Chemical Engineering Syracuse UniversitySyracuseNYUSA BioInspired Institute for Material and Living Systems Syracuse UniversitySyracuseNYUSA Department of Mechanical&Aerospace Engineering Syracuse UniversitySyracuseNYUSA Department of Electrical Engineering&Computer Science Syracuse UniversitySyracuseNYUSA Department of Biomedical Engineering University of North TexasDentonTXUSA

Organoid Intelligence ushers in a new era by seamlessly integrating cutting-edge organoid technology with the power of artificial ***,three-dimensional miniature organ-like structures cultivated from stem cells,offer an unparalleled opportunity to simulate complex human organ systems in *** the convergence of organoid technology and AI,researchers gain the means to accelerate discoveries and insights across various *** intelligence algorithms enable the comprehensive analysis of intricate organoid behaviors,intricate cellular interactions,and dynamic responses to *** synergy empowers the development of predictive models,precise disease simulations,and personalized medicine approaches,revolutionizing our understanding of human development,disease mechanisms,and therapeutic *** Intelligence holds the promise of reshaping how we perceive in vitro modeling,propelling us toward a future where these advanced systems play a pivotal role in biomedical research and drug development.

关键词： Organoids Machinelearning Deep learning Artificial intelligence Stem cells