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1.
文章依据塔里木河下游段现有的2000—2020年的地下水监测数据,对生态输水地下水前后水面线方程进行拟合,并在水均衡原理的基础上,对经过了21次生态输水之后的塔里木河下游段地下水埋深时空变化特征进行分析,以此对地下水的补给量进行估算,以更好支持后续的生态输水.  相似文献   
2.
A standard method for the extraction of tiger nut milk has been introduced. It has been shown that, although milling duration improves the yield of tiger nut milk solids and its nutrient composition, there is a quantifiable loss of nutrient in the pressing residue during milk extraction. Milling duration improved the colloidal stability of the milk against creaming during 16 h of storage. A higher milling intensity resulted in the aggregation of biological polymers which resulted in colloidal destabilisation. Milling improved the lightness and stability and reduced browning rate of the tiger nut milk during storage. This report is important for the production of tiger nut milk of consistent and comparable characteristics. Milling has been introduced as a processing method for the qualitative and quantitative modulation of the properties of tiger nut milk. It is recommended to develop further strategies to improve the colloidal stability of tiger nut milk as a beverage.  相似文献   
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Water Resources Management - Overexploitation of groundwater in the Malayer Plain has resulted in a continuous decline of groundwater levels over recent years with associated risks to water...  相似文献   
4.
Understanding the sources and composition of organic aerosol (OA) in indoor environments requires rapid measurements, since many emissions and processes have short timescales. However, real-time molecular-level OA measurements have not been reported indoors. Here, we present quantitative measurements, at a time resolution of five seconds, of molecular ions corresponding to diverse aerosol-phase species, by applying extractive electrospray ionization mass spectrometry (EESI-MS) to indoor air analysis for the first time, as part of the highly instrumented HOMEChem field study. We demonstrate how the complex spectra of EESI-MS are screened in order to extract chemical information and investigate the possibility of interference from gas-phase semivolatile species. During experiments that simulated the Thanksgiving US holiday meal preparation, EESI-MS quantified multiple species, including fatty acids, carbohydrates, siloxanes, and phthalates. Intercomparisons with Aerosol Mass Spectrometer (AMS) and Scanning Mobility Particle Sizer suggest that EESI-MS quantified a large fraction of OA. Comparisons with FIGAERO-CIMS shows similar signal levels and good correlation, with a range of 100 for the relative sensitivities. Comparisons with SV-TAG for phthalates and with SV-TAG and AMS for total siloxanes also show strong correlation. EESI-MS observations can be used with gas-phase measurements to identify co-emitted gas- and aerosol-phase species, and this is demonstrated using complementary gas-phase PTR-MS observations.  相似文献   
5.
This study explored whether factors related to the work environment could predict changes in body mass index (BMI) and whether the effect of psychosocial factors was dependent on baseline BMI. The sample consisted of 1,980 male employees from the Danish National Work Environment Cohort Study. Changes in BMI between 1995 and 2000 were analyzed, by multiple regression, as a function of background variables and a series of occupational variables obtained in 1995. Age, baseline BMI, job insecurity, and psychological demands predicted changes in BMI. Job insecurity and high or low psychological demands increased the likelihood of weight gain among obese employees, whereas they increased the likelihood of weight loss among employees with a low BMI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper uses X-ray absorption spectroscopy to study the electronic structure of the high-k gate dielectrics including TM and RE oxides. The results are applicable to TM and rare earth (RE) silicate and aluminate alloys, as well as complex oxides comprised of mixed TM/TM and TM/RE oxides. These studies identify the nature of the lowest conduction band d* states, which define the optical band gap, Eg, and the conduction band offset energy with respect to crystalline Si, EB. Eg and EB scale with the atomic properties of the TM and RE atoms providing important insights for identification high-k dielectrics that meet performance targets for advanced CMOS devices.  相似文献   
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Problems related to unpopular housing are not new in Britain's social rented sector. In the past, however, these have generally been associated with housing provided directly by the state through local authorities. For many, the term 'difficult to let' has become synonymous with large, ageing, poor quality estates managed under a centralised framework and subject to a long period of low investment and indifferent management. There has also been a long-standing assumption that social housing allocations systems tend to channel the most vulnerable tenants into the least desirable housing. In fact, the problem of difficult to let property is now as pervasive in the not-for-profit sector managed by housing associations as it is within council housing. In many cases the developments affected are small in scale and, in a significant proportion of cases, recently constructed. In explaining why property becomes difficult to let, the local and regional context is clearly important. The balance between social, economic and housing demand circumstances and property and estate characteristics varies between regions. There is relatively little evidence that difficult to let housing association properties are occupied by disproportionate numbers of the most severely disadvantaged tenants and this suggests that something has happened to modify the segregating effects of allocations systems observed in earlier studies. Nevertheless, this apparent change must be seen within the context of the general trend towards a residual role for social housing in its entirety. The social class and income range of new social sector tenants now is much diminished by comparison with earlier decades with few distinctions between the occupiers of difficult to let and other housing.  相似文献   
10.
An inulin syrup made from Jerusalem artichoke tubers, either in its commercial form or after ultrafiltration, was freeze-dried and used as a prebiotic ingredient in the small-scale manufacture of wafer crackers. The flours used for the preparation of wafer batters were from wheat, rye or spelt wheat, or 1:1 combinations of wheat flour and rye flour or wheat flour and spelt wheat flour. Batter viscosity was strongly influenced by the selection of the flour type, but remained within technologically acceptable limits. The ultrafiltration of the inulin syrup, using a 1 kDa membrane, resulted in a significant reduction of the content of free sugars and minerals which, in turn, had a significant impact on the CIE-Lab color values of the wafer crackers. Using spelt wheat flour instead of wheat flour significantly increased wafer cracker firmness measured by penetration, as did the incorporation of ultrafiltered freeze-dried instead of native freeze-dried Jerusalem artichoke syrup. Sensory analysis revealed a significant influence of product formulation on appearance, flavor and texture of the wafer crackers. It can be concluded from quality scores, which were calculated by using weighting factors assigned to the sensory attributes, that wheat flour may be partially replaced by rye flour or spelt wheat flour without negatively affecting the sensory properties of the wafer crackers.  相似文献   
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