检索结果-南通市图书馆

粉末活性炭改善MBBR处理效果的工程应用实例

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

水处理技术 2024年第7期50卷 139-143页

作者：桑军强赵锐高峰曹晓磊中石化石油化工科学研究院有限公司北京100083

在某炼化企业高浓度污水处理系统的MBBR反应器中投加75 mg/L的粉末活性炭,从工程应用的角度考察了活性炭投加后MBBR的运行效果。工业装置运行结果表明,在MBBR系统的缺氧单元空床停留时间4 h、好氧MBBR反应器空床停留时间16 h、进水COD≤... 详细信息

在某炼化企业高浓度污水处理系统的MBBR反应器中投加75 mg/L的粉末活性炭,从工程应用的角度考察了活性炭投加后MBBR的运行效果。工业装置运行结果表明,在MBBR系统的缺氧单元空床停留时间4 h、好氧MBBR反应器空床停留时间16 h、进水COD≤600 mg/L、氨氮≤40 mg/L、TN≤45 mg/L的运行条件下,MBBR系统保持了长期稳定运行,出水水质满足了设计要求。该工程实例表明,在MBBR装置中少量投加粉末活性炭,是提高在用MBBR装置运行稳定性和处理效果的一个简单、可行且有效的方法。

关键词： MBBR 活性炭炼化污水生物膜活性污泥

Comparison of Mg^(2+)- and Ca^(2+)-enhancing anaerobic granulation in an expanded granular sludge-bed reactor

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2014年第11期57卷 1596-1601页

作者： cao xiaolei SHENG YuXing cao HongBin ZHANG Yi National Key Laboratory of Biochemical Engineering and Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Graduate University of Chinese Academy of Sciences

The mechanisms responsible for the fast granulation of anaerobic sludge caused by Mg2+ and Ca2+ addition was examined in four lab-scale expanded granular sludge bed(EGSB) reactors. Results indicated that both Mg2+ and Ca2+ accelerated the sludge-granulation process and increased the amount of polysaccharides and proteins in the sludge. Energy dispersive x-ray spectrometry(EDX) analysis revealed that, in a mature granule, both Mg2+ and Ca2+ composed as phosphate and calcium was distributed primarily in the periphery of the granule, while magnesium distributed mainly in the interior. The addition of Mg2+ was more favorable for the nuclei formation, whereas the addition of Ca2+ was more favorable for subgranule growth and maintaining the granules' rigid structure. Results showed that the addition of Mg2+ in the nuclei formation stage and Ca2+ in the granule-growth stage accelerated granulation more than adding only one of them in the granulation process.

关键词： anaerobic granulation Ca2+ augmentation EPS Mg2+ augmentation

AWK-TIS:An Improved AK-IS Based on Whale Optimization Algorithm and Truncated Importance Sampling for Reliability Analysis

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第5期135卷 1457-1480页

作者： Qiang Qin xiaolei cao Shengpeng Zhang Aerospace Science and Industry Corporation Defense Technology Research and Test Center Beijing100854China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing100084China

In this work,an improved active kriging method based on the AK-IS and truncated importance sampling(TIS)method is proposed to efficiently evaluate structural *** novel method called AWK-TIS is inspired by AK-IS and RBF-GA previously published in the *** innovation of the AWK-TIS is that TIS is adopted to lessen the sample pool size significantly,and the whale optimization algorithm(WOA)is employed to acquire the optimal Krigingmodel and themost probable point(MPP).To verify the performance of theAWK-TISmethod for structural reliability,four numerical cases which are utilized as benchmarks in literature and one real engineering problem about a jet van manipulate mechanism are *** results indicate the accuracy and efficiency of the proposed method.

关键词： Structural reliability active kriging whale optimization algorithm AK-IS

Spatial distribution of bacterial community in EGSB reactor treating synthetic sulfate-containing wastewater at low organic loading rate

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2014年第1期59卷 54-61页

作者： Kai Zhang xiaolei cao Yuxing Sheng Hongbin cao National Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Graduate University of Chinese Academy of Sciences

Given that the consumption of organic substances entails costly biodesulfurization,the characteristics of the bacterial community in a reactor should be determined to increase the desulfurizing rate under low organic loading *** this study,the bacterial community distribution in the expanded granular sludge bed reactor used to treat sulfate-containing wastewater with low organic loading rate was determined by polymerase chain reaction-denaturing gradient gel electrophoresis(PCRDGGE)and 16S rDNA clone library *** results showed that the predominant bacteria were stable and accounted for*90%sulfate removal *** in band positions and intensities indicated that the distribution and abundance of bacteria were affected by their positions in the *** bands were identified in the bacterial community comprising Desulfovibrio,Desulfomicrobium,Thiomonas,Acinetobacter,Bacteroidetes,and *** functions in the reactor were also *** possible links between the functional and microbial responses were also investigated based on the characteristic and spatial distribution of each bacterium in consortium.

关键词： EGSB反应器有机负荷率硫酸盐废水细菌群落空间分布合成废水 PCR-DGGE 膨胀颗粒污泥床反应器

Designing efficient proxy signature schemes for mobile communication

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2008年第2期51卷 183-195页

作者： LU RongXing DONG xiaolei cao ZhenFu Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China

Proxy signature is an active cryptographic research area, and a wide range of literatures can be found nowadays suggesting improvement and generalization of existing protocols in various directions. However, from the efficiency view, many proposed proxy signature schemes in these literatures are not satisfying and cannot fit to the mobile communication. Therefore, there is a desire to design efficient proxy signature schemes. Based on Boneh et al＇s pairing-based short signature, this paper presents two proxy signature schemes. One is proxy-protected signature scheme, and the other is proxy aggregate signature scheme. Since both of them can achieve high efficiency, it is believed that they are specially suitable for mobile communication environment.

关键词： proxy signature proxy protected signature proxy aggregate signature bilinear pairings provable secure,efficiency

Identity-based signature scheme based on quadratic residues

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2007年第3期50卷 373-380页

作者： CHAI ZhenChuan cao ZhenFu DONG xiaolei Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Identity-based （ID-based） cryptography has drawn great concerns in recent years, and most of ID-based schemes are constructed from bilinear parings. Therefore, ID-based scheme without pairing is of great interest in the field of cryptography. Up to now, there still remains a challenge to construct ID-based signature scheme from quadratic residues. Thus, we aim to meet this challenge by proposing a concrete scheme. In this paper, we first introduce the technique of how to calculate a 2^lth root of a quadratic residue, and then give a concrete ID-based signature scheme using such technique. We also prove that our scheme is chosen message and ID secure in the random oracle model, assuming the hardness of factoring.

关键词： ID-based signature quadratic residue factoring random oracle proven security

THRESHOLD PROXY RE-SIGNATURE

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2011年第4期24卷 816-824页

作者： Piyi YANG Zhenfu cao xiaolei DONG Department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China.

The focus of this paper is to design an efficient and secure solution addressing the semi trusted issue in proxy re-signature schemes, i.e., the proxy knows the re-signature key from user A to user B, so he is able to translate any signatures made by user A to user B, which damages the essential requirement （＂non-repudiation＂ property） of proxy re-signature schemes. In this paper, the authors first define the security model for threshold proxy re-signature scheme, and then propose two threshold proxy re-signature schemes based on Ateniese-Hohenberger＇s and Shao-cao-Wang-Liang＇s approach.

关键词： Proxy re-signature robust threshold unforgeable.

New designing of cryptosystems based on quadratic fields

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2008年第8期51卷 1106-1116页

作者： DONG xiaolei cao ZhenFu WANG LiCheng Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

This paper proposes a method to construct new kind of non-maximal imaginary quadratic order （NIQO＊） by combining the technique of Diophantine equation and the characters of non-maximal imaginary quadratic order. It is proved that in the class group of this new kind of NIQO＊, it is very easy to design provable secure cryptosystems based on quadratic field （QF）. With the purpose to prove that this new kind of QF-based cryptosystems are easy to implement, two concrete schemes are presented, i.e., a Schnorr-like signature and an EIGamel-like encryption, by using the proposed NIQO＊. In the random oracle model, it is proved that：（1） under the assumption that the discrete logarithm problem over class groups （CL-DLP） of this new kind of NIQO＊ is intractable, the proposed signature scheme is secure against adaptive chosen-message attacks, i.e., achieving UF-CMA security; （2） under the assumption that the decisional Diffie-Hellman problem over class groups （CL-DDH） of this new kind of NIQO＊ is intractable, the enhanced encryption in this paper is secure against adaptive chosen-ciphertext attacks, i.e., reaching IND-CCA2 security.

关键词： public key cryptosystem quadratic field cryptography quadratic fields provable security

Effects of additive gases on dimethyl ether conversion through dielectric barrier discharge

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2009年第4期18卷 441-444页

作者： Baowei Wang xiaolei cao Yigang Yan Genhui Xu Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering Technology 7ianjin University Tianjin 300072 China

Effects of additive gases on dimethyl ether （DME） conversion through dielectric barrier discharge （DBD） were investigated. Most of the additive gases tested in this work increased the conversion of DME, but decreased the yield of liquid product. However, the addition of O2 markedly increased both the conversion of DME and the yield of liquid product. The results show that when O2 volume fraction was 39.95%, the conversion of DME was close to 100% and the yield of liquid product reached 34.43%. Different additive gases resulted in different mass fractions variation of components in liquid products.

关键词： dielectric barrier discharge plasma dimethyl ether additive gas