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排序方式: 共有229条查询结果,搜索用时 31 毫秒
91.
Bio-hydrogen production from thin stillage using conventional and acclimatized anaerobic digester sludge 总被引:1,自引:0,他引:1
Noha NasrElsayed Elbeshbishy Hisham Hafez George Nakhla M. Hesham El Naggar 《International Journal of Hydrogen Energy》2011,36(20):12761-12769
To assess the viability of biohydrogen production from thin stillage, a comparative evaluation of anaerobic digester sludge (ADS) and acclimatized anaerobic digester sludge (AADS) for biohydrogen production over a wide range of S0/X0 ratio (0.5-8 gCOD/gVSS) was performed. A maximum hydrogen yield of 19.5 L H2/L thin stillage was achieved for the AADS while tests with ADS achieved a maximum yield of only 7.5 L H2/L thin stillage. The optimum range of S0/X0 ratio for hydrogen production was found to be 1 to 2 gCOD/gVSS using conventional ADS and 3 to 6 gCOD/gVSS using AADS. The biomass specific hydrogen production rate for the AADS was 3.5 times higher than rate for the ADS throughout the range of S0/X0 ratio examined in this study. The DGGE profiles of the 16S rDNA gene fragments confirmed the superior performance of the AADS over the ADS, showing that the widely known hydrogen producers Clostridium acetobutyricum, Klebsiella pneumonia, Clostridium butyricum and Clostridium pasteurianum were the predominant species. 相似文献
92.
Hesham Shahbunder Cheol Ho Pyeon Tsuyoshi Misawa Jae-Yong Lim Seiji Shiroya 《Annals of Nuclear Energy》2010
The subcritical multiplication factor ks and the external neutron source efficiency φ∗ are important parameters in the accelerator-driven system (ADS) performance assessment. The theoretical relation between ks and the effective multiplication factor keff in a subcritical system is discussed in different cases of subcritical system. On the basis of the theoretical background, the dependence of ks and φ∗ on subcriticality, source position, and energy is numerically investigated using a simple thermal subcritical model. For the sake of experimental evaluation of ks and φ∗, the ADS experiments have been carried out in the subcritical systems combined with 14 MeV pulsed neutrons of the Kyoto University Critical Assembly (KUCA). The ks and φ∗ parameters are successfully measured by utilizing the reaction rate distribution obtained by the optical fiber detectors in the subcritical system, within a relative difference of less than 7% and 12% for ks and φ∗, respectively, between measured and calculated values for most studied cases. 相似文献
93.
Basic experiments are carried out in the Kyoto University Critical Assembly (KUCA) to study the nuclear characteristics of the accelerator-driven systems (ADS) and to establish a new neutron source for research. A method for measuring the neutron multiplication in the subcritical system is proposed by utilizing the reaction rate distribution obtained by the optical fiber detector. A comparison between the measured and calculated neutron multiplication shows agreement within a relative difference of 5% in most cases, through introducing certain correction factors. 相似文献
94.
Abdallah Y. M. Elzanaty Hesham Mostafa Rania Shalabi K. 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(5):1051-1065
Protection of Metals and Physical Chemistry of Surfaces - The effect of adding 5 and 10% of TiB2 on the corrosion of Udimet 700 (U700) in 1 M HCl including altered concentrations of organic... 相似文献
95.
Dr. Teshome L. Aboye Dr. Adam A. Strömstedt Dr. Sunithi Gunasekera Dr. Jan G. Bruhn Dr. Hesham El‐Seedi Dr. K. Johan Rosengren Dr. Ulf Göransson 《Chembiochem : a European journal of chemical biology》2015,16(7):1068-1077
Naturally occurring cystine knot peptides show a wide range of biological activity, and as they have inherent stability they represent potential scaffolds for peptide‐based drug design and biomolecular engineering. Here we report the discovery, sequencing, chemical synthesis, three‐dimensional solution structure determination and bioactivity of the first cystine knot peptide from Cactaceae (cactus) family: Ep‐AMP1 from Echinopsis pachanoi. The structure of Ep‐AMP1 (35 amino acids) conforms to that of the inhibitor cystine knot (or knottin) family but represents a novel diverse sequence; its activity was more than 500 times higher against bacterial than against eukaryotic cells. Rapid bactericidal action and liposome leakage implicate membrane permeabilisation as the mechanism of action. Sequence homology places Ec‐AMP1 in the plant C6‐type of antimicrobial peptides, but the three dimensional structure is highly similar to that of a spider neurotoxin. 相似文献
96.
Establishing a Novel Methodology to Correlate the Macroscopic and Microscopic Degree of Sintering in Magnetite Pellets during Induration
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97.
Salah A. M. Elmoselhy Waleed F. Faris Hesham A. Rakha 《Journal of Mechanical Science and Technology》2014,28(10):4139-4149
Supercharged diesel engines are a key source of hazardous regulated emissions that have been extensively modelled, yet without explainable mathematical trends. The present paper demonstrates the analytical modeling of the percentage of unburned Hydrocarbon and the HC emission rate in four-stroke diesel engines for trucks. The study presents as well the analytical modeling of the supercharged air density. A sensitivity analysis has been conducted on these developed models. The study shows that the average percentage of deviation of the simulated results from the corresponding freeway cycles field data on the percentage of unburned Hydrocarbon and the HC emission rate is 10.6% and 4%, respectively. The corresponding coefficient of determination is 70% and 83%, respectively. The relative error of the developed models of the percentage of unburned Hydrocarbon and the HC emission rate is 10.6% and 2%, respectively. The study demonstrates with 99% coefficient of determination that the average percentage of deviation of the simulated results from the corresponding field data under the steady speed operating condition for all freeway cycles on the supercharged air density is 3.7%. The relative error of the developed model of the supercharged air density is 4%. These values of relative error are in an order of magnitude of deviation that is less than that of widely recognized models in the field of vehicle powertrain modeling, such as the CMEM. These developed analytical models serve as widely valid models that follow entirely from the principles of physics and the results of these developed models have explainable mathematical trends. The fact that these developed models are dimensionally correct further supports the validity of these models. The present models can help in better analyzing the performance of diesel engines and in developing and assessing the performance of these engines. 相似文献
98.
Several modern lightweight space structures utilize curved and continuous compression members, although the behaviour of these members is not well understood. In many cases, the members are subjected to eccentric loading, which creates another difficulty in predicting their behaviour. Understanding the behaviour of curved and continuous members is certainly essential for the accurate modelling of the structures that use them, and for the reliable prediction of their strength, ductility and overall performance. The generic study presented in this paper uses theoretical and nonlinear numerical analyses to quantify the effect of curvature, continuity and load eccentricity on the behaviour of compression members. The work, although fundamental in nature, is of significant benefit to practical designs involving curved compression members. 相似文献
99.
Pest Control Expert System for Tomato (PCEST) 总被引:4,自引:0,他引:4
This paper presents a real-life pest control expert system for tomato. The system involves two main subtasks, namely: ‘diagnose’
and ‘treat’. The ‘diagnose’ subtask finds out the causes of the growers' complaints, while the ‘treat’ subtask finds out a
treatment plan for these causes. CommonKADS methodology has been used to develop the system. Dependency network is used as
one of our knowledge representation schemes in both subtasks. An expert system evaluation methodology has been suggested and
applied to the developed system.
Received May 1998 / Revised January 1999 / Accepted in revised form May 1999 相似文献
100.
Sk Raziul Ahasan Kaisarul Islam Mohammad Monirujjaman Khan Mehedi Masud Gurjot Singh Gaba Hesham A. Alhumyani 《计算机系统科学与工程》2022,40(2):673-689
In this paper, a novel and compact ultra-wideband (UWB) antenna with band-notched characteristics for body-centric communication is examined and implemented. The shape of the designed antenna looks like a ‘swan’ with a slotted patch. The performance parameters of this antenna for both the free space and on-body scenario for body-centric communication are analyzed and investigated through the simulation process using Computer Simulation Technology (CST). This antenna can avoid the interference caused by Wireless Local Area Network (WLAN) (5.15–5.825 GHz) and Worldwide Interoperability for Microwave Access (WiMAX) (5.25–5.85 GHz) systems with a band notch because of newly designed UWB antenna is revised small form factor sized. At first, the performance parameters like return loss response, gain, radiation patterns, and radiation efficiency on the free space of this UWB antenna are evaluated. After that, the on-body performance parameters of the antenna are also examined to place the antenna at various distances like 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm away from 3-layers of phantom body model at frequencies of 3.5 GHz, 5.2 GHz, 5.8 GHz, 8 GHz, and 10 GHz. All the on-body performance parameter results are compared and analyzed with free space performance parameter results. Lastly, by changing patch slot length and ground plane length, parametric studies were done for performance comparison. Due to its compact size, novel shape and significant on-body performance, the proposed antenna is very suitable for multi-purpose healthcare applications and sports performance monitoring. 相似文献