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Grassland cultivation is the key measure for restoring “Black Beach,” the extremely degraded alpine meadow in the Three River Headwater Area of the Qinghai–Tibetan Plateau. In this study, we examined the inter-specific relationship in the vegetation community of cultivated grasslands with different restoration times through the network analysis method. The results showed that with the extension of restoration time, the development of cultivated grassland would lead to increasing neutral interactions among the plant species. The proportion of species with positive and negative associations in the community decreased, while the number of species-independent pairs increased significantly. The complexity of plant interspecific association (species network density) had more influence on community stability with the extension of recovery time, which can be used to quantify the characteristics of community structure.

One new isoindolinone lactam lithocarlactam A (1) and one new triterpene lithocarin D (2), along with nine known natural products (3–11) were isolated from the broth extract of marine fungus Phomopsis lithocarpus FS508, which was isolated from a deep-sea sediment sample. Their structures were elucidated by interpretation of spectroscopic analysis and comparison with previously published literatures for the known compounds. Moreover, compounds 1 and 2 were evaluated for cytotoxic activity against SF-268, MCF-7, HepG-2, and A549 cell lines. However, both of them showed no activity against the tumor cell lines.

Caused by the expansion construction of large-scale wind farm, wind turbines of different rotor-diameters always exist in typical area with abundant wind resources. This paper investigates the wake characteristics of turbines with different rotor-diameters and their wake interactions as well as performance through LiDAR measurement and SCADA data. The experiment wind farm is located in North China with a flat terrain and three different types of wind turbines are installed. Results show that the wake recovery is related to the rotor diameter, the larger of the turbine, the slower of its wake recovery. The wake of downwind turbine is aggravated by the upstream turbine’s wake, reflected in broader wake width, larger velocity deficit and depth. Meanwhile, the upstream wind turbine’s wake that close to the downstream wind turbine can also be affected, reflected in the velocity deficit and the wake width suddenly increases when the wake approaching the downwind turbine. The power loss caused by wake effect increased sharply when wind speed decreases and the wake of a 1.5 MW wind turbine makes a great power loss even after a long distance, thus, the wake effect of large wind turbine should be paid more attentions.

选取青藏高原三江源区'黑土滩'型退化草地上建植的人工草地为研究对象，对不同建植年限人工草地植物群落及其各功能群的物种组成、平均高度、盖度和地上生物量及植物多样性等进行实地调查和对比分析，探讨'黑土滩型'退化草地在人工恢复过程中植物群落组成和多样性变化，以期回答人工恢复的草地植物群落何时才能接近天然草地、人工恢复的时间阈值应为多长等问题，从而为三江源区'黑土滩'型退化草地的恢复重建提供科学的理论指导。研究结果表明：草地恢复前5年内，禾本科植物的数量大量增加，植物群落的高度增加了847.6%，植物群落盖度增加了134.5%；不同恢复年限的草地植物群落的多样性指数都有相似的变化趋势，恢复8年后植物群落组成达到阶段性的稳定状态，在恢复时间达16-18年后，逐渐向更稳定的状态转化；恢复18年的草地与天然草地植物群落的Jaccard及Sorensen相似度指数分别为0.596、0.747，Cody差异度指数为9.5。由此可见，建植人工草地的方式恢复退化草地，可在建植8年后达较好的恢复效果；恢复时间达16年以上的人工草地采取适度的调控措施，有利于其向天然草地恢复演替；建植18年的人工草地物种组成情况与天然草地最接近，但仍有差异。因此，'黑土滩'型退化草地的人工促进恢复，到未退化的状态至少需要18年以上。

Depression is one of the prevalent and persistent psychiatric illnesses. It brings heavy socioeconomic burden such as healthcare expenditures and even higher suicide rates. Despite many hypotheses about its mechanism have been put forward, so far it is still unclear, not to mention the precise and effective diagnostic or therapeutic methods. In this paper, the current conditions of pathological and pharmacological mechanism of depression were reviewed systematically. Firstly, the most recent hypotheses and metabolomics based research including hereditary, neurotransmitter systems, brain derived neurotrophic factor (BDNF), hyperactivity of the hypothalamic pituitary adrenal (HPA) axis and inflammatory as well as metabolomics were summarized. Secondly, the present situation and development on antidepressant drugs at home and abroad were reviewed. Finally, a conclusion and prospect on the pathological and pharmacological mechanism of depression were provided primarily.

Traditionally, finely dispersed metal catalysts have been formed by reduction of precursors within mesoporous supports. A new concept for designing catalysts with enhanced activities and selectivities is to infuse presynthesized nanocrystals with well-defined morphologies into ordered mesoporous materials. The decoupling of nanocrystal synthesis and infusion provides exquisite control of the nanocrystal size, morphology, and dispersibility within the pores. A dispersion of iridium nanocrystals was infused into mesoporous silica by expanding the solvent toluene with supercritical CO2. To achieve high nanocrystal loadings, up to 1.3 wt %, we tuned the solvent quality to strengthen the interactions of the nanocrystals with the pore walls, but without precipitating the nanocrystals in the bulk solvent. Z-contrast STEM indicates conclusively that the iridium nanocrystals were located within the pores and not on the external silica surface. High catalytic activity was observed for 1-decene hydrogenation, which ...

Depression is a serious common mental disease and complex psychiatric illness often associated with stressful events. Metabonomics, which has been applied in evaluation of mechanisms of depression and

Near-infrared Fourier transform Raman spectroscopy was used to study the surface-enhanced Raman spectroscopy (SERS) behavior of nicotinamide adenine dinucleotide (NAD) on a gold electrode. It was found that the quality of SERS can be largely improved by using a near-infrared laser as the exciting source. Many bands, which cannot be enhanced in conventional SERS excited by visible light, can be observed clearly in FT-SERS. The potential, pH, and concentration dependence of the SERS revealed that NAD adsorbed on a gold electrode can be opened to a certain extent. Either the adenine or the nicotinamide moiety may change their adsorption states during the potential scanning process. The FT-SERS of NAD exhibits quite different properties from conventional SERS in two aspects: (1) the spectrum is quite dependent on applied voltages not only in peak intensities, but also in band positions; in visible excited SERS, NAD and its analogues showed no potential dependence or only manifested changes in peak intensities; (2) a small peak coupled with the ring breathing vibration band of the nicotinamide moiety appeared and increased with a negative shift of the potential. In contrast, only a single peak for this mode appeared in visible excited SERS. In addition, a very interesting phenomemon was observed in that a group of new bands appeared in the positive potential region which are similar to those with NAD binding a dehydrogenase enzyme. These results imply strongly that a charged and roughened electrode may be useful as an artificial enzyme model.

Ground source heat pump for cooling-dominated commercial buildings may utilize supplemental cooling towers to reduce system first cost and to improve system performance. The use of hybrid ground source heat pump (HGSP) can reduce the size of the ground-loop heat exchanger. Degradation of the heat pump performance due to the excess heat in the ground can be avoided by offsetting the annual load imbalance in the bore field. The operating performance and energy consumption of GSHP are analyzed in different operating and control strategies based on experimental results. A comparative study is presented that investigates the advantages and disadvantages of various system operating and control strategies.

Based on the analysis of Energy-saving technologies in current telecommunication industry, the paper analyzed the Energy-saving renovation of air conditioning in IDC Plant in Langfang. The technologies including introducing fresh air directly and air heat exchanging with isolated type were compared. According to the load characteristic of the air conditioning in plant and outdoor climate conditions in Langfang, the technology using outdoor fresh air cooling the plant is feasible. Beside, the economic analysis was also worked to carry out that natural cool source could reduce the operation energy consumption of air conditioning, realize power saving rate over 30%, recovery period below 2.5 year, so it has favorable economic and social benefits.

With the development of mining economy and the exploitation of mining technology, deep well mining has become a trend. The technical requirements of mine thermal environment are getting higher and higher. It can not effectively solve the problem of mining high-temperature by using the general cooling ways. With general ways, the system needs to consume a large amount of energy. At the same time by using of Freon refrigerant, it will emit a lot of greenhouse gases. All of these are not in conformity with the relationship between the requirements of sustainable development and the vital interests of human development. In this paper, the program of vortex tube cooling in deep well has been advanced. Vortex tube has advantages of simple structure, no moving parts, working stability and has a wide-range working scope. It has been applied in some respects. It has a large cooling speed and does not use the Freon refrigerant. This paper conducted a feasibility analysis of vortex tube cooling, proved that vortex tube cooling in deep well meet the cooling needs, has a better economic efficiency at the same time has highly energy and environmental benefits. Vortex tube cooling in deep well realizes the energy-saving and emission reduction in the true sense.

With the development of mining economy and the exploitation of mining technology, deep well mining has become a trend. The technical requirements of mine thermal environment are getting higher and higher. It can not effectively solve the problem of mining high-temperature by using the general cooling ways. With general ways, the system needs to consume a large amount of energy. At the same time by using of Freon refrigerant, it will emit a lot of greenhouse gases. All of these are not in conformity with the relationship between the requirements of sustainable development and the vital interests of human development. In this paper, the program of vortex tube cooling in deep well has been advanced. Vortex tube has advantages of simple structure, no moving parts, working stability and has a wide-range working scope. It has been applied in some respects. It has a large cooling speed and does not use the Freon refrigerant. This paper conducted a feasibility analysis of vortex tube cooling, proved that vortex tube cooling in deep well meet the cooling needs, has a better economic efficiency at the same time has highly energy and environmental benefits. Vortex tube cooling in deep well realizes the energy-saving and emission reduction in the true sense.

In the cobalt (II)-dimethylglyoxime-NH3-NH4Cl (pH 9) system, tne complex Co(II)A2 exhibits a sensitive polarographic wave. The mechanism of this catalytic wave has been investigated by linear potential sweep voltammetry, cyclic voltammerty and anedic stripping voltammetry. The experimental evidences showed that a zero-valence “active cobalt” or its complex formed during the irreversible reduction of Co(II)A2, which is adsorbed on the mercury electrode surface, and simultaneously DMG is catalytically reduced by this “active cobalt”. The mechanism of this system with the conflicting explanations of a catalytic hydrogen wave or only adsorptive complex wave is discussed.

In the 0.1M acetate buffer solution, at pH 5.9, alizarin complexone exhibits a reversible adsorptive prewave. On the surface of DME, the adsorption of alizarin complexone obeys Frumkin adsorption isotherm. In the same buffer solution, when the thulium was added, a sensitive adsorptive complex wave of thulium-alizarin complexone has been obtained by single-sweep polarograph. The composition of the complex and the mechanism of electrode processes were studied in detail.