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991.
992.
A comparative study on energy use and cost analysis of potato production under different farming technologies in Hamadan province of Iran 总被引:1,自引:0,他引:1
The aim of this study was to determine the amount of input–output energy used in potato production and to make an economic analysis of potato production in Hamadan province, Iran. Data for the production of potatoes were collected from 100 producers by using a face to face questionnaire method. The population investigated was divided into two groups. Group I was consisted of 68 farmers (owner of machinery and high level of farming technology) and Group II of 32 farmers (non-owner of machinery and low level of farming technology). The results revealed that 153071.40 MJ ha−1 energy consumed by Group I and 157151.12 MJ ha−1 energy consumed by Group II. The energy ratio, energy productivity, specific energy, net energy gain and energy intensiveness were calculated. The net energy of potato production in Group I and Group II was 4110.95 MJ ha−1 and −21744.67 MJ ha−1, respectively. Cost analysis showed that total cost of potato production in Groups I and II were 4784.68 and 4172.64 $ ha−1, respectively. The corresponding, benefit to cost ratio from potato production in the surveyed groups were 1.09 and 0.96, respectively. It was concluded that extension activities are needed to improve the efficiency of energy consumption in potato production. 相似文献
993.
The plastic deformation behavior of Al–22 wt% Ag alloy during phase transformation was investigated by studying the creep
behavior under cyclic stress reduction of low frequencies. The cyclic creep curves obtained describe clearly the cyclic stress
acceleration behavior. Increasing frequency of cyclic stress reduction enhanced the creep deformation depending upon the combination
of the experimental variables as testing temperature, aging temperature and static creep rate. The irregularity in the creep
parameters, n, β and εst with increasing aging temperatures, has been explained on the basis of structure transformations occurring in Al–Ag system
and their mode of interaction with mobile dislocations. 相似文献
994.
Yassin AE Alanazi FK El-Badry M Alsarra IA Barakat NS Alanazi FK 《Drug development and industrial pharmacy》2009,35(3):297-304
The basic objectives of this study were to prepare and characterize solid dispersions of poorly soluble drug spironolactone (SP) using gelucire carriers by spray-drying technique. The properties of the microparticles produced were studied by differential scanning calorimetry (DSC), scanning electron microscopy, saturation solubility, encapsulation efficiency, and dissolution studies. The absence of SP peaks in DSC profiles of microparticles suggests the transformation of crystalline SP into an amorphous form. The in vitro dissolution test showed a significant increase in the dissolution rate of microparticles as compared with pure SP and physical mixtures (PMs) of drug with gelucire carriers. Therefore, the dissolution rate of poorly water-soluble drug SP can be significantly enhanced by the preparation of solid dispersion using spray-drying technique. 相似文献
995.
A combined process integration and fuel switching strategy for emissions reduction in chemical process plants 总被引:1,自引:0,他引:1
The combustion of fossil fuel to provide process heating is the major source of atmospheric pollution. Combustion products such as carbon dioxide, oxides of sulfur, oxides of nitrogen and particulates are known to be the major causes for global warming, acid rains and smog. This paper presents a combined method of fuel switching and heat exchanger network (HEN) retrofit to reduce flue gas emissions. The method is demonstrated using pre-heat train of a crude oil distillation unit as the case study. Target emissions reduction of 50% is achieved at an approximate payback period of 0.44 year on the capital investment due to the combination of the two methods. 相似文献
996.
Anish Khan Aftab Aslam Parwaz Khan Mahmoud A. Hussein Bernaurdshaw Neppolian Abdullah M. Asiri 《中国化学工程学报》2019,27(2):459-466
It is necessary to synthesize new material for the advancements of the technology. In this study, new and novel poly(2-anisidine)@zirconium tungstate(P2A/ZrW_2O_8) was synthesized by simple so-gel method. Physicochemical characterization of P2A/ZrW_2O_8 was done by thermogravimetric analysis(TGA), scanning electron microscopy(SEM), X-ray powder diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), ion exchange and simultaneous four probe dc conductivity studies. The conductivity study revealed its highly semiconducting nature, in the range of 10~(-1)–10~(-2) S·cm~(-1). Ion-exchange capabilities of the composite make it applicable for cation-exchange studies. The result of distribution studies(Kd) revealed its selectivity towards Cd~(2+) compared to other metal ions. This property of the composite was utilized for designing Cd~(2+) selective membrane electrode. Several important physical parameters of the ion-selective electrode were determined, such as Nernstian slope(32.32 mV·decade~(-1)), working pH range was 2.0–4.0 and response time was found ~ 17 s.The analytical utility of this wave like composite membrane electrode was as, indicator electrode in various potentiometric titrations. 相似文献
997.
Effect of muscle type,aging technique,and aging time on oxidative stability and antioxidant capacity of beef packed in high‐oxygen atmosphere
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998.
The present paper reports a numerical investigation of spatial optimization of heat-exchanger by acting on its positioning in the vehicle’s cooling module. This analysis also elucidates how to act on the different parameters influencing heat-exchanger performance in order to optimize their functioning. A two-dimensional computation code permits optimizing the performance of the cooling module by positioning different heat exchangers, in both the driving and stop phases of the vehicle. The ultimate aim is to apply new control approaches to real vehicles so as to reduce pump and compressor energy consumption and thus fuel consumption. Compared to a reference “in-series” configuration of the cooling module HXs (in which the different HXs are superposed in the airflow direction), an “in-parallel” configuration (in which the different HX surfaces are in a row with respect to the air flow direction) increases the thermal power of the HXs by 4.4% and decreases the pressure losses by 0.9%. 相似文献
999.
Mervat Mohamed Ibrahim Mohamed Mahmoud Mourad Adel Abdelmonem Nofal Ahmed I. Z. Farahat 《International Journal of Cast Metals Research》2017,30(2):61-69
Ductile cast iron was developed by adding Aluminium (up to16 wt%Al). Effects of aluminium on microstructure, hardness, oxidation resistance at high temperature and damping capacity of cast iron were studied. Adding Al up to 4.0 wt% raised degree of graphitisation. More than 4.0 wt% up to 13.8 wt%Al showed precipitation of hard carbides. Hardness was increased signi?cantly by increasing Al due to formation of intermetallic compounds. More than 5.8 wt%Al showed a higher oxidation resistance due to formation of complex Fe-Al oxide, acted as a protective and adherent scale. Damping capacity of 2.6 and 4.0 wt%Al was increased as the volume fraction of graphite increased as well as the change of graphite from spheroidal to compacted ones. Damping capacity of 16 wt%Al was enhanced due to high ferrite (86%) containing graphite. However, decreasing of ferrite and disappearing of graphite as well as presence of carbides highly deteriorated damping capacity of 5.8, 9, 12.8 and 13.8 wt%Al cast iron. 相似文献
1000.
Abbasi Somayyeh Aliofkhazraei Mahmoud Mojiri Hedayat Amini Mina Ahmadzadeh Mohammad Shourgeshty Masoud 《Protection of Metals and Physical Chemistry of Surfaces》2017,53(3):573-578
Protection of Metals and Physical Chemistry of Surfaces - Purpose of this article is to study corrosion behavior of pure magnesium and AZ31 magnesium alloy in electrolyte containing different... 相似文献