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1.
长期施肥对棕壤有机碳储量及固碳速率的影响   总被引:8,自引:0,他引:8  
利用棕壤肥料长期定位试验,研究了不同施肥条件下棕壤有机碳在0~60 cm土层的含量和储量特征以及土壤固碳速率.试验共设6个处理,即氮磷肥有机肥配施(M_2NP)、氮肥有机肥配施(M_2N)、单施有机肥(M_2)、单施氮肥(N)、氮磷肥配施(NP)和不施肥处理(CK).结果表明:经过31年长期不同施肥,各处理土壤有机碳(SOC)含量和储量的剖面分布均呈现随土层深度增加而显著降低的规律.本试验条件下M_2NP、M_2N、M_2、NP、N、CK处理的耕层有机碳富集系数分别为0.465、0.455、0.407、0.48_2、0.393、0.471,表明耕层土壤对有机碳的保持强度最强.在0~60 cm土层土壤有机碳储量表现为M_2NP、M_2NM_2、NPNCK,有机肥和化肥配施能够显著提高土壤有机碳含量和储量.与试验前相比,CK处理各土层土壤有机碳含量和储量均显著降低.各处理碳库管理指数(CPMI)表现为M_2NPM_2NM_2NNPCK.分析不同施肥处理土壤固碳速率可知,与试验前相比,CK处理表现为碳的净释放,固碳速率达-401.4 kg·hm~(-_2)·a~(-1);固碳速率最高的为M_2NP,M_2N,分别达到489kg·hm~(-_2)·a~(-1)、440._2 kg·hm~(-_2)·a~(-1).综合结果表明,化肥、有机肥配施所产生交互效应更有利于棕壤有机碳储量的增加及固碳速率的提高.  相似文献   
2.
The purpose of this review is to describe the various aspects of pressure-sensitive adhesives prepared from natural rubber. Pressure-sensitive adhesives (PSAs) adhere instantaneously to a variety of surfaces upon application of slight pressure and can be obtained using different technologies. PSAs are materials that develop tack for low pressures and short contact times. There are number of factors affecting the adhesion property of natural rubber based pressure-sensitive adhesives. In this review, factors affecting adhesion property such as tack, peel and shear are examined in light of their relevance to adhesion in addition to measurement methods of each of the three major adhesion properties. This review paper covers the work being carried out from the last 20 years in the field of natural rubber based pressure sensitive adhesives.  相似文献   
3.
Environmental Science and Pollution Research - This study utilized the Pooled Mean Group estimator to investigate the effect of renewable energy consumption, electricity consumption, economic...  相似文献   
4.
Environmental Science and Pollution Research - Biotic invasions can predominantly alter the dynamics, composition, functions, and structure of natural ecosystems. Social insects, particularly ants,...  相似文献   
5.
Excessive use of pesticides poses increased risks to non target species including humans. In the developing countries, lack of proper awareness about the toxic potential of pesticides makes the farmer more vulnerable to pesticide linked toxicities, which could lead to diverse pathological conditions. The toxic potential of a pesticide could be determined by their ability to induce genetic mutations and cytotoxicity. Hence, determination of genetic mutation and cytotoxicity of each pesticide is unavoidable to legislate health and safety appraisal about pesticides. The objective of current investigation was to determine the genotoxic and cytotoxic potential of Endosulfan(EN) and Lambda-cyhalothrin(LC); individually and in combination. 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide(MTT) assay was utilized to determine cytotoxicity, while two mutant histidine dependent Salmonella strains(TA98, TA100) were used to determine the mutagenicity of EN and LC.Moreover, mutagenicity assay was conducted with and without S9 to evaluate the effects of metabolic activation on mutagenicity. Even though a dose dependent increase in the number of revertant colonies was detected with EN against both bacterial strains, a highly significant(p 〈 0.05) increase in the mutagenicity was detected in TA98 with S9. In comparison, data obtained from LC revealed less mutagenic potential than EN. Surprisingly,the non-mutagenic individual-concentrations of EN and LC showed dose dependent mutagenicity when combined. Combination of EN and LC synergistically induced mutagenicity both in TA98 and TA100. MTT assay spotlighted comparable dose dependent cytotoxicity effects of both pesticides. Interestingly, the combination of EN and LC produced increased reversion and cytotoxicity at lower doses as compared to each pesticide, concluding that pesticide exposure even at sub-lethal doses can produce cytotoxicity and genetic mutations, which could lead to carcinogenicity.  相似文献   
6.

The purpose of this study is to investigate the customer-based brand equity (CBBE) of green brands and their impact on green purchase consumption with the moderating effect of religious commitment. Data were gathered from 315 consumers in three large cities in Pakistan and further analysed by partial least square. The results of this study revealed that there is a significant positive nexus between CBBE and green purchase consumption. Additionally, results showed the evidence of religious commitment moderating the relationship between CBBE and green purchase consumption. The findings are helpful to the greening companies, suggesting that they should focus on every component of brand performance in order to achieve the higher ranked performance that ultimately initiates green purchase and repurchase consumption. This research addresses the attitude behaviour gap in green purchase consumption by incorporating the contingent impact of religious commitment.

  相似文献   
7.
The contemporary debate on globalization and gender equality has a strong impact on economic growth. The present study analyzes the impacts of globalization and gender parity on economic growth in the Organization of Islamic Cooperation (OIC) 47 member countries for the period (1991–2017), using System GMM panel data technique. The results of system GMM have also been empirically estimated by making two groups (viz., low-income and high-income OIC member countries from the World Bank data classification, 2019) to examine the robustness of globalization and gender parity on economic growth. The results reveal that there is a negative impact of globalization on economic growth in the overall sample of OIC countries. When estimated by decomposing low-income countries and high-income countries, globalization has a significantly positive impact on economic growth in the case of high-income OIC countries, whereas globalization slashes GDP in the case of low-income OIC countries. The study finds that there is a positive impact of gender parity (ratio of female to male labor force work participation) on economic growth. Moreover, foreign remittances, government expenditures, capital formation, and human capital are also becoming the causes of a significant increase in economic growth in OIC member countries.  相似文献   
8.
Environmental Science and Pollution Research - Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic compounds which are emitted through incomplete combustion of organic materials, fossil fuels,...  相似文献   
9.
Oropharyngeal cancer is a significant public health issue in the world. The incidence of oropharyngeal cancer has been increased among people who have habit of chewing smokeless tobacco (SLT) in Pakistan. The aim of present study was to evaluate the concentration of nickel (Ni) in biological samples (whole blood, serum) of oral (n?=?95) and pharyngeal (n?=?84) male cancer patients. For comparison purposes, the biological samples of healthy age-matched referents (n?=?150), who consumed and did not consumed SLT products, were also analyzed for Ni levels. As the Ni level is very low in biological samples, a preconcentration procedure has been developed, prior to analysis of analyte by flame atomic absorption spectrometry (FAAS). The Ni in acid-digested biological samples was complexed with ammonium pyrrolidinedithio carbamate (APDC), and a resulted complex was extracted in a surfactant Triton X-114. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by FAAS. The chemical variables, such as pH, amounts of reagents (APDC, Triton X-114), temperature, incubation time, and sample volume were optimized. The resulted data indicated that concentration of Ni was higher in blood and serum samples of cancer patients as compared to that of referents who have or have not consumed different SLT products (p?=?0.012–0.001). It was also observed that healthy referents who consumed SLT products have two to threefold higher levels of Ni in both biological samples as compared to those who were not chewing SLT products (p? Figure
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10.
Abstract

This study introduces a two-stage interval-stochastic programming (TISP) model for the planning of solid-waste management systems under uncertainty. The model is derived by incorporating the concept of two-stage stochastic programming within an interval-parameter optimization framework. The approach has the advantage that policy determined by the authorities, and uncertain information expressed as intervals and probability distributions, can be effectively communicated into the optimization processes and resulting solutions. In the modeling formulation, penalties are imposed when policies expressed as allowable waste-loading levels are violated. In its solution algorithm, the TISP model is converted into two deterministic submodels, which correspond to the lower and upper bounds for the desired objective-function value. Interval solutions, which are stable in the given decision space with associated levels of system-failure risk, can then be obtained by solving the two submodels sequentially. Two special characteristics of the proposed approach make it unique compared with other optimization techniques that deal with uncertainties. First, the TISP model provides a linkage to prede?ned policies determined by authorities that have to be respected when a modeling effort is undertaken; second, it furnishes the reflection of uncertainties presented as both probabilities and intervals. The developed model is applied to a hypothetical case study of regional solid-waste management. The results indicate that reasonable solutions have been generated. They provide desired waste-flow patterns with minimized system costs and maximized system feasibility. The solutions present as stable interval solutions with different risk levels in violating the waste-loading criterion and can be used for generating decision alternatives.  相似文献   
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