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41、Biomass and carbon storage of Eucalyptus and Acacia plantations in the Pearl River Delta, South China

摘要:Forest plantations represent an important carbon sink. In the Pearl River Delta (PRD) in Southern China, fast-growing Eucalyptus and Acacia are favoured plantation species, but little is known regarding their efficiency with respect to biomass production, partitioning and dynamics with stand age, or the contribution made by the understory, litter and coarse woody debris (CWD) to the volume of biomass and fixed carbon. Here, a set of 21 plantations of various ages were monitored for the pattern of biomass accumulation and partitioning. A continuous biomass expansion factor (BEF) method was applied to a set of forest inventory data (FID) over the periods 1989-2003 to estimate biomass accumulation, carbon storage and its pattern of change over time. The accumulation of biomass increased with stand age, reaching, respectively, 207.45 and 189.35tha −1 in mature Eucalyptus and Acacia plantations. The contribution of secondary biomass from the understory, litter layer and CWD accounted for, respectively, up to 10.2% and 20.3% of the total biomass in the two types of plantation, highlighting the significance of secondary biomass. At a similar growth stage, the ranking of the contribution to secondary biomass in the Eucalyptus plantations was litter>herbaceous plants>shrubs>CWD, while in the Acacia plantations, it was litter>CWD>shrubs>herbaceous plants. The Eucalyptus and Acacia plantations in the PRD accumulated some 2.66-7.84Mt of biomass and sequestered 1.33-3.92Mt of carbon. For both species, the bulk of the plantations (Eucalyptus 82.1%, Acacia 89.3%) were at the young to middle-aged stage. The Acacia plantations generated a higher biomass density than the Eucalyptus plantations. Forest management intensification and reforestation programmes, especially targeting Acacia or mixed Eucalyptus/Acacia forests, offer good potential for future carbon sequestration.
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42、Criteria for assessing the ecological risk of nonylphenol for aquatic life in Chinese surface fresh water

摘要:The typical environmental endocrine disruptor nonylphenol is becoming an increasingly common pollutant in both fresh and salt water; it compromises the growth and development of many aquatic organisms. As yet, water quality criteria with respect to nonylphenol pollution have not been established in China. Here, the predicted 「no effect concentration」 of nonylphenol was derived from an analysis of species sensitivity distribution covering a range of species mainly native to China, as a means of quantifying the ecological risk of nonylphenol in surface fresh water. The resulting model, based on the log-logistic distribution, proved to be robust; the minimum sample sizes required for generating a stable estimate of HC5 were 12 for acute toxicity and 13 for chronic toxicity. The criteria maximum concentration and criteria continuous concentration were, respectively 18.49 μg L−1 and 1.85 μg L−1. Among the 24 sites surveyed, two were associated with a high ecological risk (risk quotient >1) and 12 with a moderate ecological risk (risk quotient >0.1). The potentially affected fraction ranged from 0.008% to 24.600%. The analysis provides a theoretical basis for both short- and long-term risk assessments with respect to nonylphenol, and also a means to quantify the risk to aquatic ecosystems.• The minimum sample size was 12 for acute and 13 for chronic NP toxicity. • Both maximum and continuous concentration criteria were derived for NP. • NP pollution presented a low to moderate risk in Chinese surface fresh waters.
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43、Characterization of household food waste and strategies for its reduction: A Shenzhen City case study

摘要:A clear understanding of the characteristics of generated household food waste (HFW) is necessary to formulate an effective food waste management policy. The present study has focused on the quantity and composition of generated HFW as well as the driving forces, and further explored potential means of reducing HFW. The quantity of avoidable HFW generated in Shenzhen City in 2015 was estimated to be two-fold greater than that in 2001, which consequently produced 1,378 thousand metric tonnes CO2 eq. emissions during their ultimate waste disposal. This suggests that HFW prevention can yield great environment benefits by reducing carbon emissions. Based on a survey in which 418 households in Shenzhen City participated, it was apparent that both household size and income are the major drivers to HFW generation. A substantial reduction in HFW generation can be achieved through improvements in consumer behaviors, consciousness and attitudes. Priority should be given to the strategies that can increase people’s awareness of HFW induced problems, with the purposes to achieve a more sustainable development.
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44、An integrated approach to identify critical transcription factors in the protection against hydrogen peroxide-induced oxidative stress by Danhong injection

摘要:Oxidative stress plays a vital role in many pathological processes of the cardiovascular diseases. However, the underlying mechanism remains unclear, especially on a transcription factor (TF) level. In this study, a new method, concatenated tandem array of consensus transcription factor response elements (catTFREs), and an Illumina-based RNA-seq technology were integrated to systematically investigate the role of TFs in hydrogen peroxide (H2O2)-induced oxidative stress in cardiomyocytes; the damage was then rescued by Danhong injection (DHI), a Chinese standardized product approved for cardiovascular diseases treatment. The overall gene expression revealed cell apoptosis and DNA repair were vital for cardiomyocytes in resisting oxidative stress. By comprehensively integrating the transcription activity of TFs and their downstream target genes, an important TFs-target network were constructed and 13 TFs were identified as critical TFs in DHI-mediated protection in H2O2-induced oxidative stress. By using the integrated approach, seven TFs of these 13 TFs were also identified in melatonin-mediated protection in H2O2-induced damage. Furthermore, the transcription activity of DNA-(apurinic or apyrimidinic site) lyase (Apex1), Myocyte-specific enhancer factor 2D (Mef2d) and Pre B-cell leukemia transcription factor 3 (Pbx3) was further verified in pluripotent stem cell-derived cardiomyocytes. This research offers a new understanding of cardiomyocytes in response to H2O2-induced oxidative stress and reveals additional potential therapeutic targets. The combination of two parallel omics datasets (corresponding to the transcriptome and proteome) can reduce the noise in high-throughput data and reveal the fundamental changes of the biological process, making it suitable and reliable for investigation of critical targets in many other complicated pathological processes.
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45、Enzymic degradation of hydroxyethyl cellulose and analysis of the substitution pattern along the polysaccharide chain

46、最新室内细部设计实例集. IV, 健身. 娱乐建筑. IV, Sport. recreation 2007

47、In situ studies of the spiral growth of zinc thiourea sulphate crystals with ethylene diamine tetraacetic acid doped by atomic force microscopy

摘要:Investigation of crystal growth under screw dislocation mechanisms on the (100) face of zinc tris (thiourea) sulphate (ZTS) crystals doped ethylene diamine tetraacetic acid (EDTA) has been carried out in a fluid cell by in situ atomic force microscopy (AFM). The generation of a dislocation spiral during the step advancing was observed. Through the measurement of the critical length of four sides of a rectangular spiral with a complete growth period, the advancement velocities, step edge free energies and kinetic coefficients of steps have been obtained. The changes in the step velocity with time have been studied. It was found that the relationship between the step velocity and step length is inconsistent with the previous report. The emergent points of dislocations do not disappear even though they are covered by either several elementary steps or macro-steps. It is also shown that the interchange of two spirals whose emergent points of dislocations are adjacent will lead to a distortion of two contiguous steps and affect the growth rates of spirals. The obviously asymmetric growth of spirals of opposite sign in real time was observed. The coexistence and competition of dislocation spirals under different conditions was emphasized considering the activity of dislocation.Investigation of crystal growth on the (100) face of zinc thiourea sulphate crystals doped ethylene diamine tetraacetic acid has been carried out by in situ atomic force microscopy. The generation of a dislocation spiral, the relevant thermodynamic and kinetic parameters, the interchange of double spirals and the growth of spirals of opposite sign were studied. In addition, the coexistence and the competition of dislocation spirals in real time were discussed.
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48、In situ atomic force microscopy studies of growth mechanisms and surface morphology of zinc thiourea sulfate crystal

摘要:In situ atomic force microscopy (AFM) has been utilized in studies of the growth mechanism on the (100) face of zinc tris (thiourea) sulphate (ZTS) crystals growing from solution. The growth on the (100) face of pure ZTS crystal is mainly controlled by two dimensional (2D) nucleation mechanisms, under which the hillock is formed through layer-by-layer growth. It is easier to form 2D nuclei at edge dislocation and the apex of steps. The growth of 2D nucleus is in accord with nucleation-spreading mode. The growth rate along the 〈010〉 direction is faster than that along 〈001〉 direction, both of which increase firstly and then decrease with the spread of nucleus. The kinetic coefficients of one nucleus have been roughly estimated to be 3.6 × 10−4 cm/s and 1.8 × 10−4 cm/s in two directions, while the activation energy E was calculated to be 53.7 kJ/mol and 55.4 kJ/mol, respectively. The 2D nuclei can be generated under lower supersaturation with the addition of EDTA. If there are several hillocks growing together, step bunches will form when the steps moving in the same direction meet each other, while the meeting of steps that move in the inverse direction will result in the separation of steps. The ability of nucleation of edge dislocation outcrops are different even they are close to each other on the same surface. When the nucleus was generated at the edge dislocation sites, it cannot spread speedily until finishes an 「incubation period」. Moreover, the detour of microsteps was observed due to the existence of pits. If the microcrystals attached on the surface block the step advancement, or leave the surface or are covered by the macrosteps, the pits are formed. If the macrosteps advanced across the pits, the pits will be covered and the liquid inclusions may form. However, if the microcrystal forming in the pit grow up and expose on the surface, the pit will not be covered by macrosteps. The formation of solid inclusions may be caused by the microcrystals being embedded into the single steps which move layer-by-layer.In situ atomic force microscopy has been utilized in studies of the growth mechanism on the (100) face of zinc tris (thiourea) sulphate crystals growing from solution. The growth on the (100) face of pure ZTS crystal is mainly controlled by two dimensional nucleation mechanisms. The spread of nuclei, advancement of steps and formation of pits are studied. The kinetic parameters are also roughly estimated.
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49、新移民文学 :融合与疏离 2009

摘要:本书敏锐地观察到20世纪80年代以来新移民作家不同于以往第一代移民作家创作的情况, 从飞散写作的角度, 将从事华文写作的新移民作家和从事居住国语言写作的新移民作家作为一个创作整体展开思考, 沟通了中国现当代文学, 比较文学, 外国文学研究的相关领域,提出了一些新的学术思考点,...
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50、酉阳清源 2009

摘要:"本书是乌江流域酉阳县清源遗址发掘成果的系统报告. 全书分前言, 地层堆积和新石器时代遗存, 商周时期遗存, 历史时期遗存, 出土动物骨骼等六章, 以商周时期的遗存为重点, 对灰坑、房址、水井、墓葬等遗迹和陶、石、骨、青铜等质地的遗物做了详尽地报告和初步地分析研究"--内容简介.
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51、徐詩 :二卷 2009

52、寺社參詣と庶民文化 2009

53、浮生六记 2009

54、Temperature-dependent birefringence of lithium triborate, LBO in the THz regime

55、Isotropic Paper Directly from Anisotropic Wood: Top-Down Green Transparent Substrate Toward Biodegradable Electronic

56、Plasmonic Wood for High-Efficiency Solar Steam Generation

摘要:Plasmonic metal nanoparticles are a category of plasmonic materials that can efficiently convert light into heat under illumination, which can be applied in the field of solar steam generation. Here, this study designs a novel type of plasmonic material, which is made by uniformly decorating fine metal nanoparticles into the 3D mesoporous matrix of natural wood (plasmonic wood). The plasmonic wood exhibits high light absorption ability (≈99%) over a broad wavelength range from 200 to 2500 nm due to the plasmonic effect of metal nanoparticles and the waveguide effect of microchannels in the wood matrix. The 3D mesoporous wood with numerous low-tortuosity microchannels and nanochannels can transport water up from the bottom of the device effectively due to the capillary effect. As a result, the 3D aligned porous architecture can achieve a high solar conversion efficiency of 85% under ten-sun illumination (10 kW m−2). The plasmonic wood also exhibits superior stability for solar steam generation, without any degradation after being evaluated for 144 h. Its high conversion efficiency and excellent cycling stability demonstrate the potential of newly developed plasmonic wood to solar energy-based water desalination.3D plasmonic wood is directly derived from the natural wood by a uniformly anchored layer of metal nanoparticles. The black, 3D plasmonic wood with numerous open and aligned mesoporous channels has a high light absorption (≈98%) and solar energy conversion efficiency of ≈85% under ten-sun illumination.
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57、Development and Validation of Digital Enzyme-Linked Immunosorbent Assays for Ultrasensitive Detection and Quantification of Clostridium difficile Toxins in Stool

58、Active Semi-supervised Community Detection Algorithm with Label Propagation

摘要:Community detection is the fundamental problem in the analysis and understanding of complex networks, which has attracted a lot of attention in the last decade. Active learning aims to achieve high accuracy using as few labeled data as possible. However, so far as we know, active learning has not been applied to detect community to improve the performance of discovering community structure of complex networks. In this paper, we propose a community detection algorithm called active semi-supervised community detection algorithm with label propagation. Firstly, we transform a given complex network into a weighted network, select some informative nodes using the weighted shortest path method, and label those nodes for community detection. Secondly, we utilize the labeled nodes to expand the labeled nodes set by propagating the labels of the labeled nodes according to an adaptive threshold. Thirdly, we deal with the rest of unlabeled nodes. Finally, we demonstrate our community detection algorithm with three real networks and one synthetic network. Experimental results show that our active semi-supervised method achieves a better performance compared with some other community detection algorithms.
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59、In situ studies of the spiral growth of zinc thiourea sulphate crystals with ethylene diamine tetraacetic acid doped by atomic force microscopy In situ studies of the spiral growth of zinc thiourea sulphate crystal

60、In situ atomic force microscopy studies of growth mechanisms and surface morphology of zinc thiourea sulfate crystals In situ atomic force microscopy studies of growth mechanisms…

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