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Enzymes are an important class of biomacromolecules which catalyze many metabolic processes in living systems. Nanomaterials can be synthesized with tailored sizes as well as desired surface modifications, thus acting as promising enzyme regulators. Fluorescent gold nanoclusters (AuNCs) are a representative class of ultrasmall nanoparticles (USNPs) with sizes of ∼2 nm, smaller than most of proteins including enzymes. In this work, we chose α-chymotrypsin (ChT) and AuNCs as the model system. Activity assays and inhibition kinetics studies showed that dihydrolipoic acid (DHLA)-coated AuNCs (DHLA-AuNCs) had a high inhibitory potency (

With the extensive application of silver containing materials in industry, the issue of release of silver ions has attracted increasing attention due to toxic effect of silver ions on the human health and environment. Traditionally, silver ions can be detected by atomic absorption spectroscopy, atomic emission spectrometry etc., which needed expensive and elaborate instruments and were high energy consumption. Therefore, economic and convenient methods are required for the effective determination of silver ions. Herein, two types of carbon dots (CDs-1 and CDs-2) have been prepared through a solvothermal synthesis method by using sucrose or citric acid and tris(hydroxymethyl)aminomethane as precursor, respectively. Then, CDs-1 were developed for the detection of silver ions through a colorimetric method. The detection mechanism was based on the reduction of silver ions and the formation of silver nanoparticles, which possess unique surface plasma resonance properties. CDs-1 could both act as reductants and stabilizers during the reaction for determination of silver ions. This CDs-1 based detection system could quantitatively determine silver ions in 3 min with a limit of detection (LOD) of 26 nmol/L (2.81 ppb). Interestingly, this strategy could also realize the detection of silver ions by CDs-2. Furthermore, the sensing assay is applicable to detecting silver ions in lake water and silver sulfadiazine cream samples.

Under the framework of "Kyoto Protocol", CDM mechanisms and the formation of carbon financial markets supply a platform for developing countries to participate in the global greenhouse gas emission reduction activities. PCDM projects will be the inevitable choice in the area of energy-saving construction. This paper analyzes the CDM mechanism and the applied limitations of CDM in the field of energy-saving residential building and then it points out the potential of PCDM in Chinese energy-saving construction and finally puts forward suggestions for promoting the residential building PCDM projects

The information system of construction market supervision and business management based on Web includes three subsystems, which are construction market supervision, management of bid and tender for construction project, and application of construction project and this thesis adopts the combinative method of prototyping and structured life cycle to develop and study on the information system. First, it integrally plans and lies out by adopted structured method. Then, it analyzes the mode and content of construction supervision, and the flow of construction business and construction project application, gives the prototyping system of them. Then it considers the requirement and function demand of the users, improves the prototyping system, establishes a scientific flow, and analyzes its data flow. And then, it designs the integral structure of the system by adopted system structure based on Web, designs the network structure by adopted three layer B/S distributing system, and gives the detailed design of the code, database, input and output of the system. Finally, it gives the technical demand of the build of the integral network system, gives the demand of the software and hardware system structure, and displays the windows of the main function of the system.

In the paper, an approach for introducing a photoacid generator (PAG) into Langmuir- Blodgett (LB) films to draw photopatterns is described. The chemically amplified positive-tone resist system used here consisted of two components: a copolymer, poly(iso-pentylmethacrylamide- co-4-t-butyloxylvinylphenylcarbonate) [poly(iPMA-t-BVPC39)] and a photoacid generator (PAG), tri(2,3-dibrompropyl)iso-cyanvrate (TDBPIC). In the two-component system, the acid generated by the photoacid generator (PAG) catalyzes the deprotection reaction of poly(iPMA-t-BVPC39) to re- move the tert-butoxycarbonyl group (t-BOC) in the exposed region during the post exposure baking process, thus rendering the exposure region soluble to alkali aqueous to form a positive tone. Phhot- olithographic properties of the LB films have been evaluated. The patterns can be resolved with a resolution of 1 μm line width by UV irradiation,followed by development with an alkali solution. Quantum yield is determined to be 0.065 and catalytic chain length is also calculated to be 2460. The LB films used above can be used to generate etched gold patterns on a glass substrate using an aqueous iodide, ammonium iodide in alcohol /water，as the etchant. The etch resistance of such LB films is sufficiently good, allowing patterning of a gold film suitable for photomask fabrication.