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301.
For a commutative ring R and a faithfully flat R-algebra S we prove,under mild extra assumptions,that an R-module M is Gorenstein flat if and only if the left S-module S?_R M is Gorenstein flat,and that an R-module N is Gorenstein injective if and only if it is cotorsion and the left S-module Hom R(S,N)is Gorenstein injective.We apply these results to the study of Gorenstein homological dimensions of unbounded complexes.In particular,we prove two theorems on stability of these dimensions under faithfully flat (co-)base change. 相似文献
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Amin Said Amin Prof. Dr. Dr. Dietmar Lerche Ahammed Suhail Odungat Sven Uwe Boehm Dr. Thomas Koch Dr. Fatih Özcan Prof. Dr. Doris Segets 《ChemCatChem》2024,16(6):e202301393
Hansen Solubility Parameters (HSP), viewed in the context of similarity whenever dispersion is focused, offer valuable insights into the surface characteristics of nanoparticles. However, existing methods for determining HSP via the sedimentation of nanoparticles require multiple probe liquids, resulting in time-consuming, costly experiments with potential health risks. To address this, we developed a two-step strategy that enables a systematic selection of liquids. The key element of the approach is to first identify the rough location of the Hansen sphere in the three-dimensional Hansen space using a well-chosen set of probe liquids of different polarities and chemical structures. Then, depending on the outcome of the first step, a particular choice of liquids is made for the final HSP determination. Taken together, the introduced procedure reduces the amount of required liquids for experiments from currently more than ten to a maximum of seven chosen based on a well-defined, coherent methodology. Validation was performed on carbon black, non-pigmentary nano-scale titania, silicon/carbon composites, and lanthanum cobaltite particles, i. e., relevant materials that are commonly utilized in fuel cells, batteries, cyclohexene oxidation, catalytic combustion, photocatalysis, and heterogeneous Fenton reactions. The study showcases the potential to save time, costs, and efficiently determine HSP values in a comparable manner. 相似文献
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Fatih Camci 《The Journal of the Operational Research Society》2014,65(9):1423-1436
The Travelling Salesman Problem (TSP) is one of the most studied problems in the literature due to its applicability to a large number of real cases. Most variants of the TSP consider total distance travelled. This paper presents a new generalised formulation of the TSP that aims to minimise the sum of functions of latencies to cities, rather than total distance travelled. Then, a new problem that uses a special function using the latency as input is presented, called the Travelling Maintainer Problem (TMP). The TMP integrates the output of prognostics in Condition-based Maintenance (CBM) with the TSP. CBM aims to minimise the failure and maintenance cost by identifying and predicting upcoming failures through the analysis of sensory information collected in real-time. Maintenance scheduling is performed using the predicted failure information obtained from the CBM. When the systems to be maintained are geographically distributed, maintenance scheduling requires integrated analysis of travel times and their effects on the failure progression in systems. This paper also presents Genetic Algorithm and Particle Swarm Optimisation-based solutions and their comparisons for the TMP on a case study. 相似文献
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Rhodium‐catalyzed transfer hydrogenation with aminophosphines and analysis of electrical characteristics of rhodium(I) complex/n‐Si heterojunctions
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Murat Aydemir Yusuf Selim Ocak Khadichakhan Rafikova Nurzhamal Kystaubayeva Cezmi Kayan Alexey Zazybin Fatih Ok Akın Baysal Hamdi Temel 《应用有机金属化学》2014,28(6):396-404
A series of novel neutral mononuclear rhodium(I) complexes of the P―NH ligands have been prepared starting from [Rh(cod)Cl]2 complex. Structural elucidation of the complexes was carried out by elemental analysis, IR and multinuclear NMR spectroscopic data. The complexes were applied to the transfer hydrogenation of acetophenone derivatives to 1‐phenylethanol derivatives in the presence of 2‐propanol as the hydrogen source. Catalytic studies showed that all complexes are also excellent catalyst precursors for transfer hydrogenation of aryl alkyl ketones in 0.1 m iso‐PrOH solution. In particular, [Rh(cod)(PPh2NH―C6H4―4‐CH(CH3)2)Cl] acts as an excellent catalyst, giving the corresponding alcohols in excellent conversion up to 99% (turnover frequency ≤ 588 h?1). Furthermore, rhodium(I) complexes have been used in the formation of organic–inorganic heterojunction by forming their thin films on n‐Si and evaporating Au on the films. It has been seen that the structures have rectifying properties. Their electrical properties have been analyzed with the help of current–voltage measurements. Finally, it has been shown that the complexes can be used in the fabrication of temperature and light sensors. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
310.
Microwave‐Assisted Synthesis of Some Novel Benzimidazole Derivatives Containing Imine Function and Evaluation of Their Antimicrobial Activity
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Bahittin Kahveci Fatih Yılmaz Emre Menteşe Musa Özil Şengül Alpay Karaoğlu 《Journal of heterocyclic chemistry》2014,51(4):982-990
4‐Bromo‐o‐phenylenediamine and ethylimido‐p‐bromophenylacetate, 1 , were subjected to microwave irradiation to synthesize benzimidazole derivative, compound 2 . Ester derivative, 3 , and hydrazide derivative, 4 , of compound 2 were also synthesized, respectively. Finally, compound 4 was treated with 11 different aromatic aldehydes to obtain benzimidazole derivatives containing imine function. All reactions were carried out with microwave irradiation and conventional heating, and results were compared. Some of the newly synthesized compounds showed moderate antimicrobial activity against some tested organisms. 相似文献