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941.
Hu Li Theodore T. Tsotsis Muhammad Sahimi S. Joe Qin 《American Institute of Chemical Engineers》2014,60(6):2063-2071
The efficient and economic production of landfill gases (LFG) by optimally adjusting LFG production settings is of high interest as a promising source of biomass energy. A key obstacle in LFG production optimization is the large‐scale and complex system with overwhelming uncertainty and heterogeneity. We propose a simplified ensemble‐based optimization (EnOpt) method to solve the LFG production optimization problem when constraints are not a concern, where the gradient information is obtained from an ensemble of realizations of the system. For constrained optimization, a novel parameterless genetic algorithm is proposed and successfully applied to the simulated LFG process. The effectiveness of the proposed (EnOpt) method and the parameterless genetic algorithm is demonstrated with the simulation of a landfill and gas generation and transport therein, using a parallel computation strategy. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2063–2071, 2014 相似文献
942.
Lessons from the Far End: Caterpillar FRASS-Induced Defenses in Maize,Rice, Cabbage,and Tomato 总被引:1,自引:0,他引:1
Swayamjit Ray Saumik Basu Loren J. Rivera-Vega Flor E. Acevedo Joe Louis Gary W. Felton Dawn S. Luthe 《Journal of chemical ecology》2016,42(11):1130-1141
Plant defenses to insect herbivores have been studied in response to several insect behaviors on plants such as feeding, crawling, and oviposition. However, we have only scratched the surface about how insect feces induce plant defenses. In this study, we measured frass-induced plant defenses in maize, rice, cabbage, and tomato by chewing herbivores such as European corn borer (ECB), fall armyworm (FAW), cabbage looper (CL), and tomato fruit worm (TFW). We observed that caterpillar frass induced plant defenses are specific to each host-herbivore system, and they may induce herbivore or pathogen defense responses in the host plant depending on the composition of the frass deposited on the plant, the plant organ where it is deposited, and the species of insect. This study adds another layer of complexity in plant-insect interactions where analysis of frass-induced defenses has been neglected even in host-herbivore systems where naturally frass accumulates in enclosed feeding sites over extended periods of time. 相似文献
943.
Taher Rahimi Aghdam Habib Mehrizadeh Dariush Salari Hui-Hsin Tseng Aligholi Niaei Azam Amini 《Korean Journal of Chemical Engineering》2018,35(4):994-999
Perovskite type BiFeO3 (BFO) was synthesized by sol-gel auto-combustion method. Synthesized BFO was immobilized on the micro slides glass plates by sol-gel dip-coating method. The sample was characterized by XRD, FESEM, UV-Vis DRS, and BET techniques. The XRD pattern confirmed the perovskite structure, and from the Debye-Scherrer equation the average crystalline size was calculated as 19 nm. The FE-SEM images of prepared BFO showed porous structure with low agglomeration. The band gap energy was calculated about 2.13 eV, and the specific surface area (SSA) of prepared BFO nanostructure was obtained 55.1m2 g?1. The photocatalytic activity of prepared pure and immobilized BFO was investigated in the removal of NOx under UV irradiation, in the batch photoreactor. The effects of operational parameters such as initial concentration of NOx, light intensity and amount of coated photocatalyst, under identical conditions, were investigated. The results showed that the highest conversion of NOx was obtained as 35.83% in the 5 ppm of NOx with 1.2 g immobilized BFO and under 15 W illumination lamp. 相似文献
944.
Shu-Kai Yeh Ying-Ru Chen Ting-Wei Kang Tzu-Jian Tseng Sheng-Ping Peng Chien-Chia Chu Syang-Peng Rwei Wen-Jeng Guo 《Journal of Polymer Research》2018,25(1):30
In this study, three different approaches were applied to obtain thermoplastic polyurethane (TPU) nanocellular foams. The TPU was synthesized with a 4, 4′-methylenebis (phenyl isocyanate) and 1, 4-butanediol (MDI/BD) hard segment system using a pre-polymer method. The three approaches included increasing the hard segment content, adding a graphene nucleation agent, and replacing the soft segments. Although the synthesized TPUs had a different hardness, it was possible to obtain nanocellular structures with all of the methods. The cell structure is not a function of hardness only. Crystallinity affects the cell structure as well. The addition of graphene and replacement of the soft segments were more effective at yielding nanocellular foams. Our best results showed that after adding 0.1 wt% of graphene, the average cell size of the TPU foam decreased to 715 nm, and the cell density was improved to 4.94 × 1011 cells/cm3. The relative density of the foam could be as low as 0.77. This study first reported elastomer-based nanocellular structures with such low relative density. 相似文献
945.
Dulce Alondra Cuevas‐Acua Saul Ruiz‐Cruz Joe Luis Arias‐Moscoso Marco Antonio Lopez‐Mata Paul Baruk Zamudio‐Flores Silvia Elena Burruel‐Ibarra Hisila del Carmen Santacruz‐Ortega 《Polymer International》2020,69(4):423-428
This study investigated the performance of chitosan based films with added, high‐intensity ultrasound‐pulsed, gelatins (42, 52, 71 and 84 W cm?2). The mechanical, structural, chemical and antioxidant properties were investigated, to evaluate the potential of ultrasound as a technique to improve film properties. The tensile strength and elastic modulus of films containing ultrasound‐pulsed gelatins showed a significant increase, while the elongation parameter showed a significant decrease. Micrographs showed that all films presented agglomerations. The infrared spectra of the films displayed characteristic shifts in the chitosan and gelatin spectra, which may be the result of hydrogen bridge interactions and electrostatic interactions between the two polymers. The antioxidant capacity was analyzed through the ferric reducing antioxidant power (FRAP) assay and the 2,2′‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS) assay of films and showed that gelatins treated with higher acoustic intensity had improved antioxidant capacity. High‐intensity ultrasound‐treated gelatin enhanced the strength, elasticity and antioxidant properties of the chitosan based films. © 2020 Society of Chemical Industry 相似文献
946.
Ching‐Fang Tseng Po‐Ju Tseng Chi‐Min Chang Yu‐Chieh Kao 《Journal of the American Ceramic Society》2014,97(6):1918-1922
Novel microwave dielectric ceramics in the Li2MnO3 system with high Q prepared through a conventional solid‐state route had been investigated. All the specimens exhibited single phase ceramics sintered in the temperature range 1140°C–1230°C. The microwave dielectric properties of Li2MnO3 ceramics were strongly correlated with sintering temperature and density. The best microwave dielectric properties of εr = 13.6, Q × f = 97 000 (GHz), and τf = ?5.2 ppm/°C could be obtained as sintered at 1200°C for 4 h. BaCu(B2O5) (BCB) could effectively lower the sintering temperature from 1200°C to 930°C and slightly induced degradation of the microwave dielectric properties. The Li2MnO3 ceramics doped with 2 wt% BaCu(B2O5) had excellent dielectric properties of εr = 11.9, Q × f = 80 600 (GHz), and τf = 0 ppm/°C. With low sintering temperature and good dielectric properties, the BCB added Li2MnO3 ceramics are suitable candidates for LTCC applications in wireless communication system. 相似文献
947.
Muhammad Ismail Chun-Yang Huang Debashis Panda Chung-Jung Hung Tsung-Ling Tsai Jheng-Hong Jieng Chun-An Lin Umesh Chand Anwar Manzoor Rana Ejaz Ahmed Ijaz Talib Muhammad Younus Nadeem Tseung-Yuen Tseng 《Nanoscale research letters》2014,9(1):45
The mechanism of forming-free bipolar resistive switching in a Zr/CeO
x
/Pt device was investigated. High-resolution transmission electron microscopy and energy-dispersive spectroscopy analysis indicated the formation of a ZrO
y
layer at the Zr/CeO
x
interface. X-ray diffraction studies of CeO
x
films revealed that they consist of nano-polycrystals embedded in a disordered lattice. The observed resistive switching was suggested to be linked with the formation and rupture of conductive filaments constituted by oxygen vacancies in the CeO
x
film and in the nonstoichiometric ZrO
y
interfacial layer. X-ray photoelectron spectroscopy study confirmed the presence of oxygen vacancies in both of the said regions. In the low-resistance ON state, the electrical conduction was found to be of ohmic nature, while the high-resistance OFF state was governed by trap-controlled space charge-limited mechanism. The stable resistive switching behavior and long retention times with an acceptable resistance ratio enable the device for its application in future nonvolatile resistive random access memory (RRAM). 相似文献
948.
Chia-Hao Lu Tzu-Yang Chao Ying-Feng Chiu Shuo-Yen Tseng Hsu-Cheng Hsu 《Nanoscale research letters》2014,9(1):178
We prepared urchin-like micron-sized ZnO cavities with high optical quality by oxidizing metallic Zn and proposed the mechanism that resulted in the growth of the urchin-like microstructures. The photoluminescence spectra of the ZnO microstructures had a predominant excitonic emission at room temperature. The lasing properties of the urchin-like ZnO microstructures were investigated systematically through excitation power- and size-dependent photoluminescence measurements. The results showed that a low lasing threshold with high quality factors could be achieved because of the high reflectivity of the optical reflectors formed by the tapered nanowires. The unique optical characteristics may facilitate the development of high-efficiency random lasers. 相似文献
949.
Teng Chang Chandrasekaran Neelakandan Thein Kyu Yu-Tsan Tseng Linda DeFine Thomas Alexander 《Polymer》2014
Development of asymmetric channel morphology driven by coagulation-induced phase separation of genistein (G) modified poly(ether sulfone)/poly(vinyl pyrrolidone) (PES/PVP) blends has been examined in relation to their miscibility phase diagram. PES/G pairs turned out to be miscible in the amorphous state, whereas solid–liquid phase separation occurred at high genistein compositions. The solid–liquid phase diagram involving the liquidus and solidus lines were computed self-consistently in the framework of the combined free energy of Flory-Huggins for liquid–liquid phase separation and phase field free energy for crystal solidification. The ternary phase diagram of PES/PVP/G blends was subsequently established that consisted of various coexistence regions. The actual amounts of genistein incorporated in the PES/PVP membranes were determined as a function of weight percent of genistein in feed. On the basis of UV-vis spectroscopy, the extent of genistein leaching during incubation in human blood was evaluated in conjunction with the PVP leaching from the blend membrane. 相似文献
950.
Jillian E. Smith Chen Liang Michael Tseng Noel Li Sha Li Allisandra K. Mowles Anil K. Mehta David G. Lynn 《Israel journal of chemistry》2015,55(6-7):763-769
Structurally defined cross-β assemblies have allowed for the development of basis sets for isotope-edited infrared spectra to follow progressive assembly over time. These basis sets, composed of a minimal number of individual spectra, are sufficient to identify the populations of polymorphs evolving throughout the assembly process. This approach provides, for the first time, the spectral assignment and relative distribution of paracrystalline intermediates formed from the intermolecular molten globule phase where nucleation occurs. Using the basis sets, we can now follow how subtle changes in assembly energetics impact the accessible polymorphs along the assembly pathway. Here, simple methylation of the Gln22 side chain of the nucleating core of the Dutch mutant of the Aβ of Alzheimer’s disease, Aβ(16-22)E22Q, dramatically increases the distribution of sampled polymorphs and slows progression to the final thermodynamic assembly. These data establish that amyloid cross-β structures can assemble through a dynamic conformational phylogeny. This fluid context-dependent network, so accessible to simple peptides, may provide the basis for the conformational selection and evolution of the complex supramolecular assemblies implicated in the many protein misfolding and prion diseases. 相似文献