Copper-based bimetallic electrocatalysts for CO_(2) reduction:From mechanism understandings to product regulations

Electrocatalytic carbon dioxide reduction reaction(CO_(2) RR)is a promising method to solve current environment and energy issues.Copper-based catalysts have been widely studied for converting CO_(2) into value-added hy-drocarbon products.Cu monometallic catalyst has been proved to have some shortcomings,including relatively high energy barriers and diverse reaction pathways,leading to low reaction activities and poor product selec-tivity,respectively.Recently copper-based bimetallic tandem catalysts have attracted extensive attentions due to their special catalyst structure,which can be easily regulated to achieve high CO_(2) RR reactivity and product selectivity.With the development of quantum chemistry calculations and spectroscopic characterization methods,deep understandings of CO_(2) RR from the mechanism perspective provide a broad horizon for the design of effi-cient catalysts.This review offers a good summary of reaction mechanisms and product regulation strategies over copper-based bimetallic catalysts,along with a brief discussion on future directions towards their practical applications.

Technical Regulations for Production of Apple ‘Jiping 1’

Apple‘Jiping 1’is a new early maturing apple variety bred by Shijiazhuang Pomology Institute,Hebei Academy of Agriculture and Forestry Sciences.To further normalize the standardized production technology of‘Jiping 1’,realize improvement and upgrading of fruit quality,and improve sustainable development of apple industry,according to national and industrial standards,specific requirements on selection of production orchard,planting,soil,fertilizer and water management,shaping and pruning,flower and fruit management,pest control,and fruit harvesting of‘Jiping 1’are put forward,and technical regulation for production of‘Jiping 1’(standard number:DB 13/T 5167-2020)is made.The regulation has important guiding significance for the production of early maturing apple in Hebei Province.

STUDIES ON STEROID PLANT-GROWTH REGULATOR 27.ENHANCED PRODUCT DIASTEREOMERIC EXCESSES IN ASYMMETRIC DIHYDROXYLATION OF THE(22E,24R)-AND THE(22E,24S)-24-ALKYL STEROIDAL UNSATURATED SIOECHAIN BY USING THE SHARPLESS IMPROVED CHIRAL LIGAND

The osmium tetroxide catalyzed asymmetric dihydroxylation of the(22E)- steroidal sidechain is described and an unexpected 8:1 ratio of(22R,23R)and (22S,23S)was obtained from the(22E,24S)-24-ethyl substituted sidechain.

Numerical Simulation of Oil and Gas Two-Phase Flow in Deep Condensate Gas Reservoirs in Bohai Buried Hills

The BZ19-6 gas field is characterized by high temperature and high pressure (HTHP), high condensate content, little difference between the formation pressure and dew point pressure, and large amount of reverse condensate liquid. During the early stage of depletion development, the production gas-oil ratio (GOR) and production capacity remain relatively stable, which is inconsistent with the conventional reverse condensate seepage law. In view of the static and dynamic conflict in development and production, indoor high-temperature and high-pressure PVT experiment was carried out to reveal the mist-like condensation phenomenon of fluids in the BZ19-6 formation. And the seepage characteristics of condensate gas reservoirs with various degrees of depletion under the condition of HTHP were analyzed based on production performance. The change rule of fluid phase state was analyzed in response to the characterization difficulties of the seepage mechanism. The fluid state was described using the miscible mechanism. And the interphase permeability interpolation coefficient was introduced based on interfacial tension. By doing so, the accurate characterization of the “single-phase flow of condensate gas-near-miscible mist-like quasi single-phase flow-oil-gas two-phase flow” during the development process was achieved. Then the accurate fitting of key indicators for oilfield development was completed, and the distribution law of formation pressure and the law of condensate oil precipitation under different reservoir conditions are obtained. Based on research results, the regulation strategy of variable flow rate production was developed. Currently, the work system has been optimized for 11 wells, achieving a “zero increase” in the GOS of the gas field and an annual oil increase of 22,000 cubic meters.

New prenylated flavonoid glycosides derived from Epimedium wushanense byβ-glucosidase hydrolysis and their testosterone production-promoting effects

Six new prenylated flavonoid glycosides,including four new furan-flavonoid glycosides wushepimedoside A–D(1–4)and two new prenyl flavonoid derivatives wushepimedoside E–F(5–6),and one know analog epimedkoreside B(7)were isolated from biotransformation products of the aerial parts of Epimedium wushanense.Their structures were elucidated according to comprehensive analysis of HR-MS and NMR spectroscopic data,and the absolute configurations were assigned using experimental and calculated electronic circular dichroism(ECD)data.The regulatory activity of compounds 1–7 on the production of testosterone in primary rat Leydig cells were investigated,and 4 and 5 exhibited testosterone production-promoting activities.Molecular docking analysis suggested that bioactive compounds 4 and 5 showed the stable binding with 3β-HSD and 4 also had good affinity with Cyp17A1,which suggested that these compounds may regulate testosterone production through stimulating the expression of the above two key proteins.

Gut Microbiota Brings a Novel Way to Illuminate Mechanisms of Natural Products in vivo

Poor bioavailability and undefined major/direct targets are two major obstacles for herbal medicines and natural products（NPs） to elucidate their precise mechanisms in vivo. Gut microbiota is an important bridge between eukayotic body and environment, which can interact with a majority of medicines with poor bioavailability and mediate their in vivo pharmacological activities. There are two main modes through which gut microbiota may mediate the pharmacological effects of NPs. First, gut microbiota catabolizes the NPs in herbal medicines into secondary metabolites with higher bioavialability and/or higher activity, facilitating the NPs enter circulation and exert beneficial impact at the pathological spot. Second, herbal medicines and NPs can favorably shift the compositional structure of gut microbiota, thereby performing remote functions to diseased organs/tissues via the systemic impaction of gut microbiota. In this review, the potential pathways were summarized through which gut microbes facilitate the pharmacological functions of herbal medicines and NPs and highlight the significance of gut microbiota in clarifying the in vivo mechanisms of herbal medicines and NPs.

OVERVIEW OF CHINA'S AUTO WINDOW REGULATOR PRODUCTION

Ⅰ. General Currently in China, there are over 50 essential enterprises which produce the window regulators for motor vehicles, with a total output of about 5 million units in 1994. The window regulator sector started with the birth of Jiefang trucks of FAW in the 50s’ and 60s’. Through several decades practice, the products can be classified according to the structure as follows: guider screw type (mainly applied to large buses and ships); parallel four-link type; single arm type, crossed arm type, etc.