建筑工程中的绿色施工管理

经济水平的提升促进了人们环保意识的增强,绿色环保观念逐渐贯彻到各个领域中,而现阶段在建筑行业中融入绿色环保观念具有十分重要的意义。基于此,文章阐述了建筑工程中绿色施工管理的目的,分析了建筑工程绿色施工中存在的问题,提出了建筑工程中绿色施工管理的策略。

Preparation of ultrafine silver powders with controllable size and morphology

The ultrafine silver powders were prepared by liquid reduction method using Arabic gum as dispersant.The effects of different dispersants,pH values,and temperature on the morphology and particle size of silver powders were investigated.It is found that Arabic gum can better adsorb on silver particles via chemical adsorption,and it shows the best dispersive effect among all the selected dispersants.The particle size of silver powders can be finely tuned from 0.34 to 4.09μm by adjusting pH values,while the morphology of silver powders can be tuned by changing the temperature.The silver powders with high tap density higher than 4.0 g/cm3 were successfully prepared in a wide temperature range of 21.8-70°C.Especially,the tap density is higher than 5.0 g/cm3 when the temperature is optimized to be 50°C.The facile process and high silver concentration of this method make it a promising way to prepare high quality silver powders for electronic paste.

The practice of project construction and management of Three Gorges ship lock

The double-line five-step ship-lock of Three Gorges Project (TGP) is an extra-large navigation structure with the maximum design total head and single-step delivery head in the world and complicated technical problems.The shiplock is a challenging and world-class project integrating the advanced techniques and equipment,the up-to-date technologies and materials,as well as the advanced project management.Through 17-year construction and 9-year operation of the ship-lock,various difficulties in design,construction,equipment manufacturing and installation as well as system debugging have been overcome effectively.The project management ideas,management system,management methods,technological innovation and team building are summarized according to the management practice of the second stage main work of Three Gorges ship-lock.

NEQM （NFC Based Equipment Qualification Management） System Preventing Counterfeit and Fraudulent Item

Qualification of equipment essential to safety in NPPs （nuclear power plants） ensures its capability to perform designated safety functions on demand under postulated service conditions. However, a number of incidents identified by the NRC （Nuclear Regulatory Commission） since 1980s catalysed the US nuclear industry to adopt standard precautions to guard against counterfeit items. The purpose of this paper is to suggest the NFC （near field communication） based equipment qualification management system preventing counterfeit and fraudulent items. The NEQM （NFC based equipment qualification management） system works with the support of legacy systems such as PMS （procurement management system） and FMS （facility management system）.

Copper/cuprous sulfide electrode: preparation and performance

Cuprous sulfide （Cu2S） is a direct band-gap p-type semiconductor with excellent ionic/electronic hybrid conductivity. Alt- hough Cu/Cu2S/sulfide or polysulfide system is adopted as counter electrode of quantum-dots-sensitized solar cells （QDSSC）, the electrode process is seldom reported. Here, the electrochemical growth of Cu2S film on a copper （Cu） surface, the redox behaviors of sulfide and polysulfide, and the all-in-solid charge-transfer properties of Cu2S film are investigated. It is clarified that the copper electrode simultaneously undergoes an activated process, a membrane growth process, and a redox phase transformation process. The solid charge-transfer capability of CuzS is quantified with a high exchange-current density of 2.27 A/cm2, which elucidates that the Cu/CuzS electrode is a qualified material for counter electrodes of QDSSC. These results aid understanding of the physicochemical mechanism of QDSSC with a polysulfide electrolyte and Cu/Cu2S counter electrode.

Preparation and properties of physically and chemically cross-linked hybrid hydrophobic association hydrogels with good mechanical strength

To correct the defects of hydrophobic association hydrogels （HA-gels）, new physically and chemically cross-linked hybrid hy- drophobic association hydrogels （hybrid HA-gels） were prepared by radical copolymerization of acrylamide （AM）, octylphe- nol polyoxyethylene （n） acrylate （OPnAC, n stands for the number of ethoxy group, and is 10 and 21） and N,N＇-methylene- bisacrylamide （MBA）. On the basis of the statistical molecular theory of rubber elastic, the Mooney-Rivlin model and using the tensile true stress （O＇true） tested at room temperature, the number of network strands per unit volume （o~） and the num- ber-average molar mass of a network strand （Me） were evaluated for hybrid HA-gels. For the hydrogels, the effect of the con- tent of MBA and OP10AC on their tensile mechanical properties was studied by using o0 and Mc; also, the effect of the com- positions and temperature on their swelling behavior in distilled water was discussed in detail. In addition, hybrid HA-gels in- cluding a small quantity of MBA possessed the capabilities of secondary self-healing and remolding. In contrast with HA-gels prepared by the same compositions besides MBA, hybrid HA-gels showed good mechanical strength and long-term thermal stability in distilled water in the range of 25 to 80℃. Furthemore, hybrid HA-gels also avoided the self-deswelling behavior of HA-gels. The results show that the application fields of HA-gels will be greatly broadened after introducing a chemical cross-linking network.