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1.
在未来勘探开发中研发的推动作用   总被引:2,自引:1,他引:1  
在过去的20年里,尽管油价和经营环境不断发生着变化,但勘探开发的产量和经济效益持续增长着,科学研究和先进技术起了关键作用。未来的勘探开发将更加依赖于先进的技术和科学的研究开发。 随着变化的经营环境和关键的先进科学技术强有力的结合,出现了新的研发模式和发展趋势。在这里我们  相似文献   
2.
Water Resources Management - Sustained pumping of groundwater can lead to declining water levels in wellfields and concerns regarding the sustainability of groundwater resources. Aquifer Storage...  相似文献   
3.
This study presents a new Y-channel design for measuring the zeta potential and surface conductance of a solid-liquid pairing using the current monitoring technique. The new design improves the throughput and reliability of the testing apparatus since the displacement between two solutions can be repeated many times without interfering with the experiments. It also increases the accuracy of the measurement by producing sharper start and end transitions for the current–time plot of the solution displacement process. In this design, efforts have been made to minimize the effects of electrolysis, Joule heating and undesired pressure driven flow on the measurements. An improvement on the current–time slope analysis is also presented. The Y-channel design was validated by comparing zeta potential measurements to published results. The zeta potential of several biological buffers relevant to the microfluidic community in plasma treated PDMS/PDMS and PDMS/Glass microchannels are presented. Preliminary studies of surface conductivity measurements using the Y-channel design were also conducted and are briefly discussed.  相似文献   
4.
This paper describes an efficient aircraft geometry design tool which is necessary for design and analysis applications through Integrated Product and Process Development (IPPD). The design process decomposes aircraft geometry into several components to represent it accurately and realistically with a reduced number of shape control parameters. For this purpose, several configuration representation algorithms are thoroughly investigated and discussed. The proposed configuration generation algorithm employs the super ellipse equation with simple analytic distribution functions, Class function/Shape function Transformation (CST) and can represent and manipulate complex shapes accurately with a small number of control parameters. A model of aircraft geometry, represented in this approach, can be applied to conceptual and preliminary stages of aircraft design and development with realistic and accurate configuration data. A Parameter-based Comprehensive Aircraft Design (PCAD) tool which implements a geometry generation process for aircraft design and optimization using customization of commercial computer-aided design software (CATIA V5) and the Product Data Management (Enovia Smarteam). The proposed configuration design tool could be especially efficient when automation, flexibility and rapid changes of geometry are required in a short time and with low computational resources.  相似文献   
5.
A series of poly(acrylic acid-co-methylvinylketone–graft–sulfamethoxazole)(AVMDS) species was synthesized for drug carrier applications. The synthesis involved two steps: copolymerization of acrylic acid(AA) with methyl vinyl ketone(MVK) through the free radical route and subsequent grafting of the sulfamethoxazole (SMX) onto the copolymer via the Schiff base reaction of the primary amine of SMX with the carbonyl groups of the MVK units. The structures and properties of the materials were characterized by nuclear magnetic resonance(NMR), X-ray diffraction(XRD), differential scanning calorimetry(DSC), and scanning electronic microscopy (SEM). An in-vitro cytotoxicity test of the drug-carrier systems via MTT assay revealed no significant cytotoxic effect at concentrations up to 100?µg?·?ml?1. The dynamic release of SMX from these systems through a retro-imidation reaction (inverse Schiff base reaction) was investigated in depth, where the diffusion through the polymer matrix, the enhancement of the water solubility of SMX, the influence of the initial drug concentration, the pH of the medium, and the effect of the degree of swelling of the polymer matrix on the release dynamics were evaluated. The AVMGS4 and AVMGS1 drug carrier systems containing 3.58 and 1.18?wt% of SMX were the best performing systems.  相似文献   
6.
Increasing energy demand has led to a substantial growth in the use of wind energy across the world, which can be attributed to the low initial and running costs and rapid and easy deployment of this technology. The development of hydrogen from wind energy is an excellent way to store the excess wind power produced, as the produced hydrogen can be used not only as clean fuel but also as input for various industries. Considering the good wind potentials of Yazd province, the variety of industries that are active in this area, and the central location of this province in Iran, which gives it ample access to major transport routes and other industrial hubs, hydrogen production from wind power in this province could benefit not only this region but the entire country. Given these considerations, we conducted a technical, economic, and environmental assessment of the potential for wind power generation and hydrogen production in Yazd province. Overall, the assessments showed that the best locations for harvesting wind energy in this province are Bahabad and Halvan stations. For these two stations, it is recommended to use EWT DW 52-900 turbine to take advantage of its higher nominal capacity to achieve higher electricity and hydrogen output and emission reduction. For Abarkoh and Kerit stations, which have a low wind energy potential, it is recommended to use small turbines such as Eovent EVA120 H-Darrieus. Also, economic and technical assessments showed that it is not economically justified to harvest wind energy in Ardakan station. The results of ranking the stations with the Step-wise Weight Assessment Ratio Analysis (SWARA) and Evaluation based on Distance from Average Solution (EDAS) techniques showed that Bahabad station was introduced as the best place to produce hydrogen from wind energy.  相似文献   
7.
Design organizations play a major role in the construction industry: they are the media that transfer the requirements of the client to the contractor and ensure that they are met. Thus they need to provide a high quality of service to ensure that their client's project achieves the best possible standards of cost, time and quality. Seventy quality practices (QP) were identified as having a bearing on the quality of service provided by the local design organizations. These quality practices were grouped into fifteen sections termed quality sections (QS). The prevalence of these practices among the local design organizations was surveyed and determined. The results indicate a significant need for improvement in the quality sections ‘working relationship’, ‘employee training and education’, and ‘performance quality audit’. The study reveals the need for the establishment of a design code, and evaluation standards for local design organizations.  相似文献   
8.
In order to improve the miscibility of poly(vinyl chloride)/polystyrene (PVC/PS) system and to use the prepared material as a membrane to separate benzene from benzene/cyclohexane mixture by pervaporation technique, two poly(styrene-co-N-vinylpyrrolidone) (PSVP) copolymers containing 6.67 and 13.55 mol% of N-vinylpyrrolidone (N-VP) contents were synthesized through a radical polymerization. A comparative study of the miscibility of the PVC/PSVP blends with different compositions was carried out using differential scanning calorimetry, viscosimetry and Fourier transform infrared spectroscopy methods in which the interaction parameters between the two components were widely investigated. To improve the pervaporative flux of PVC membrane to separate benzene from benzene/cyclohexane mixture, a preliminary test of swelling and sorption was performed on PVC/PSVP7 membranes using an azeotropic benzene/cyclohexane mixture. It was revealed that the PVC/PSVP7 membrane containing 10 wt% of PSVP7 showed the best performance and the diffusion behaviour of this mixture through PVC and PVC/PCVP7 membranes has a Fickian behaviour. The pervaporation parameters of this membrane support those of the swelling and selective sorption data and reveal that this membrane could enhance the total flux without significantly affecting its selectivity to benzene.  相似文献   
9.
A large number of experiments in a 2 cm diameter and 6 m length tube were carried out in order to study the two-phase flow regimes and pressure drops in it. The two-phase flow in the experimental tube was modeled using commercial CFD code, Fluent 6.2. An Artificial Neural Network (ANN) with three inputs including gas and liquid velocities and tube slope was designed and trained to predict average pressure drop across the tube. The comparison between CFD and ANN predictions of pressure drops with experimental measurements shows that the CFD results are more accurate than the ANN evaluations for new conditions.  相似文献   
10.
ABSTRACT: BACKGROUND: Coffee and tea consumption was hypothesized to interact with variants of vitamin D-receptor polymorphisms, but limited evidence exists. Here we determine for the first time whether increased coffee and tea consumption affects circulating levels of 25-hydroxyvitamin D in a cohort of Saudi adolescents. METHODS: A total of 330 randomly selected Saudi adolescents were included. Anthropometrics were recorded and fasting blood samples were analyzed for routine analysis of fasting glucose, lipid levels, calcium, albumin and phosphorous. Frequency of coffee and tea intake was noted. 25-hydroxyvitamin D levels were measured using enzyme-linked immunosorbent assays. RESULTS: Improved lipid profiles were observed in both boys and girls, as demonstrated by increased levels of HDL-cholesterol, even after controlling for age and BMI, among those consuming 9--12 cups of coffee/week. Vitamin D levels were significantly highest among those consuming 9--12 cups of tea/week in all subjects (p-value 0.009) independent of age, gender, BMI, physical activity and sun exposure. CONCLUSION: This study suggests a link between tea consumption and vitamin D levels in a cohort of Saudi adolescents, independent of age, BMI, gender, physical activity and sun exposure. These findings should be confirmed prospectively.  相似文献   
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