区块链服务网络的构建机理与技术实现

联盟链技术是我国区块链发展和应用的主阵地.传统联盟链应用存在底层技术平台异构、应用技术门槛高、成链成本大、运维监管难等瓶颈问题,限制了区块链技术与应用发展.提出一种区块链公用基础设施——区块链服务网络(blockchain-based service network, BSN)的构建机理,阐述BSN的技术架构和实现机制. BSN已于2020年4月在中国正式商用,能够显著降低区块链开发、部署、运维、互通和监管成本,有利于区块链技术向企业、政府、行业等领域推广应用,为我国新型智慧城市建设和数字经济发展提供了可信可控的公用基础设施和服务载体.     

EPC联合体合作关系演化博弈分析

EPC 联合体合作关系质量对项目目标能否顺利实现有着至关重要的影响。基于演化博弈理论,研究 EPC 联合体内部设计单位和施工单位之间合作关系,通过双方收益和成本得出双方合作关系支付矩阵,构建并求解演化博弈理论的复制动态方程及演化稳定策略,并应用 Matlab 软件对影响 EPC 联合体合作关系的因素进行仿真。结果表明,设计单位和施工单位合作关系长期演化结果可能是均采取“合作”策略,也可能是均采取“不合作”策略;群体采取“合作”策略的比例与额外收益分配及其分配系数、收益实现系数及“不合作”策略损失及其风险系数成正相关,与合作成本和损失分配系数成负相关。针对双方合作困境给出了改善 EPC 联合体内部各参与方合作关系质量的建议。     

手持多媒体终端的网络运作模式

对于手持多媒体终端的网络运作模式进行了对比和探讨,在参考国外系统的基础上提出适合国内市场的网络运作模式,并对该运作模式进行了详细讨论和分析.     

Application of an immobilized microbial consortium for the treatment of pharmaceutical wastewater: Batch-wise and continuous studies

In the present investigation, a microbial consortium consisting of four bacterial strains was selected for the treatment of pharmaceutical industry wastewater. The consortium was immobilized on a natural support matrix-Luffa and used for the treatment of real-time pharmaceutical wastewater in batch and continuous processes. The batch process was carried out to optimize the culture conditions and monitor the enzymatic activity. An array of enzymes such as alcohol dehydrogenase, aldehyde dehydrogenase, monooxygenase, catechol 2,3-dioxygenase and hydroquinol 1,2-dioxygenase were produced by the consortium. The kinetics of the degradation in the batch process was analyzed and it was noted to be a first-order reaction. For the continuous study, an aerobic fixed-film bioreactor (AFFBR) was utilized for a period of 61 days with variable hydraulic retention time (HRT) and organic loading rate (OLR). The immobilized microbes treated the wastewater by reducing the COD, phenolic contaminants and suspended solids. The OLR ranged between (0.56 ± 0.05) kg COD·m^-3 d^-1 to 3.35 kg COD·m^-3·d^-1 and the system achieved an average reduction of 96.8% of COD, 92.6% of phenolic compounds and 95.2% of suspended solids. Kinetics of the continuous process was interpreted by three different models, where the modified Stover Kincannon model and the Grau second-order model proved to be best fit for the degradation reaction with the constant for saturation value, KL being 95.12 g·L^-1·d^-1, the constant for maximum utilization of the substrate U_max being 90.01 g·L^-1 d^-1 and substrate removal constant K_Y was 1.074 d^-1 for both the models. GC-MS analysis confirmed that most of the organic contaminants were degraded into innocuous metabolites.     

Efficient PCR-based gene disruption in Saccharomyces strains using intergenic primers

Gene disruptions are a vital tool for understanding Saccharomyces cerevisiae gene function. An arrayed library of gene disruption strains has been produced by a consortium of yeast laboratories; however their use is limited to a single genetic background. Since the yeast research community works with several different strain backgrounds, disruption libraries in other common laboratory strains are desirable. We have developed simple PCR-based methods that allow transfer of gene disruptions from the S288C-derived strain library into any Saccharomyces strain. One method transfers the unique sequence tags that flank each of the disrupted genes and replaces the kanamycin resistance marker with a recyclable URA3 gene from Kluyveromyces lactis. All gene-specific PCR amplifications for this method are performed using a pre-existing set of primers that are commercially available. We have also extended this PCR technique to develop a second general gene disruption method suitable for any transformable strain of Saccharomyces.     

Establishment of functional rumen bacterial consortia (FRBC) for simultaneous biohydrogen and bioethanol production from lignocellulose

For simultaneous saccharification and fermentation of cellulosic bioresources to biofuels, a stable rumen-mimicking bacterial consortium was established and maintained by sub-culturing and is referred to here as the “Functional Rumen Bacterial Consortium” (FRBC). The microbial community was analyzed by denaturing gradient gel electrophoresis, which contained dominant species such as Clostridium xylanolyticum, Clostridium papyrosolvens, Clostridium beijerinckii, Clostridium puniceum, Clostridium putrifaciens, and Ruminococcus sp. These predominant Clostridial strains showed potential in converting lignocellulosic material into bio-hydrogen and bio-fuels. The Clostridial strains with 16S rRNA sequences identical to the DGGE profile were isolated from FRBC. The isolate C. puniceum strain Ru6 exhibited xylanase and pectinase activity and higher hydrogen productivity and was thus chosen as the partner strain for ethanol production with C. xylanolyticum Ru15, which showed additional endoglucanase activity. A co-culture approach was used to reconstruct the FRBC with Ru6 and Ru15, and the productivities of hydrogen and ethanol were comparable to that of the FRBC. These results demonstrate the potential of a biologically inspired rumen-mimic microbial community to produce cellulosic bio-fuels.     

Simultaneous removal of Cr(Ⅵ) and phenol in consortium culture of Bacillus sp. and Pseudomonas putida Migula (CCTCC AB92019)

The simultaneous removal of Cr(Ⅵ) and phenol in a consortium culture containing Cr(Ⅵ) reducer, Bacillus sp. and phenol degrader, Pseudomonas putida Migula (CCTCC AB92019) was studied. Phenol was used as the sole carbon source. Bacillus sp. utilized metabolites formed from phenol degradation as electron donors and energy source for Cr(Ⅵ) reduction. Optimum Cr(Ⅵ) reduction was observed at a phenol concentration of 150 mg/L and an initial Cr(Ⅵ) concentration of 15 mg/L. Both the Cr(Ⅵ) reduction and phenol degradation were influenced by the cell composition of the culture, but the phenol degradation was not significantly affected by the content of Bacillus sp. The experiments also showed that the amount of phenol degraded was more than that stoichiometrically required for Cr(Ⅵ) reduction.     

基于区块链的微电网合作博弈电力交易优化

微电网可实现分布式电源的有效整合,减少新能源间歇性波动对主网造成的影响。为更好的实现微电网的优化运行,文章提出了基于区块链和博弈理论的微电网电力交易模型。首先,建立微电网P2P(Peer-to-Peer)电力交易系统的总体架构,对区块链网络、智能合约逻辑进行设计;进一步,通过分析微电网中各用户主体的效益,优化交易过程中的用户匹配;接着,利用合作博弈算法实现微电网P2P电力交易定价模型。最后,仿真及分析结果表明,基于区块链与合作博弈的交易模型能有效实现用户间电力交易,有利于构建公开、透明、高效的市场环境,可确保用户收益最大化。     

施工技术规范和放样图在设计施工协作中的作用

通过对施工技术规范和放样图内容、作用以及二者相互关系的研究，发现二者能在设计方与施工方之间搭建一个有效沟通平台，对于改进“设计-招标-建造”模式下的设计施工协作具有非常重要的意义。在此基础上，进一步分析了我国现阶段施工技术规范和放样图方面存在的问题，并提出相应对策建议。     

国际石油工程联合体承包模式风险分析与应对

国内承包商在走出国门与国际承包商及当地承包商联合承接项目的过程中,总存在很多合作问题,这些问题反映出我国承包商对联合体特有风险的研究不足。笔者从我国工程承包公司的角度出发,探讨国际工程松散型联合体中8个方面的风险,并提出应对措施,包括慎重选择联合体合作方,细化联合体协议条款,理顺联合体内部关系及责任,优化联合体组织机构以及合理向联合体各方转移风险。