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41.
Optimizing water allocations for the agricultural sector, the main water consumer, at the beginning of a period of drought is essential. However, long-term inflow forecasting, with its high uncertainty, is a necessary component of the allocation process. This paper presents a methodology that combines this uncertainty with economic factors to determine water allocation. The following models were developed and linked: optimization of agricultural water allocation under water scarcity, long-term flow forecast and quantification of forecast uncertainties. The approach coordinates economic values of water with system operational requirements. The Zayandeh Rud dam and irrigation system was selected to explore the methodology of this research.  相似文献   
42.
The stretch formability of ultrafine-grained (UFG) interstitial-free steel (IF-steel) produced by equal-channel angular extrusion/pressing (ECAE/P) via various strain paths was investigated with a miniaturized Erichsen test. A coarse-grained (CG) sample demonstrated high formability with an Erichsen index (EI) of 4.5 mm. Grain refinement by ECAE decreased the formability, but increased the required punch load (F EI) depending on the applied strain paths. The EI values were 0.35, 2.90, and 3.91 mm for 8A-, 8Bc-, and 8C-processed samples, respectively. Decrease in the biaxial stretch formability was attributed to the limited strain-hardening capacity of the UFG microstructure. Also, the grain morphology of the UFG microstructure was found to be very influential on stretch formability. Heavily elongated grain morphology in the 8A-processed microstructure resulted in the lowest formability due to the increased cracking tendency through elongated grain boundaries. However, the UFG microstructures with equiaxed grains obtained after 8C and 8Bc ECAE resulted in better formability compared to 8A. The UFG microstructure reduced the roughness (orange peel effect) of the free surface of the biaxial stretched samples by decreasing the non-uniform grain flow leading to the so-called orange peel effect. It should be noted that the strength and ductility values gained from uniaxial tensile tests are not comparable directly to the EI and F EI values determined from the Erichsen tests. Finally, it is important to emphasize that the UFG microstructure produced by a suitable strain path leading to equiaxed grains below 1 μm could be highly deformed even under multiaxial stress conditions.  相似文献   
43.
The temperature interval ΔT SE of superelasticity in [001]-, [$ \bar 1 $ \bar 1 23]-, and [$ \bar 1 $ \bar 1 24]-oriented Co40Ni21Ga30 (at. %) single crystals strained at compression has been studied. It is established that ΔT SE in the [001]-oriented single crystal amounts to 441 K and the reversible B2-L10 martensite transformations in loaded samples take place at T 2 = 698 K. In [$ \bar 1 $ \bar 1 23]- and [$ \bar 1 $ \bar 1 24]-oriented samples, ΔT SE decreases to 233 K and the superelasticity is observed up to T 2 = 523 K.  相似文献   
44.
45.
Two inorganic–organic hybrid supramolecular compounds based on polyoxometalates formulated as (C4H8NH2)4[Mo8O26] (1) and (NH4)Na2[AsIIIMo6O21(O2CCH2NH3)3]·8H2O (2) have been synthesized by conventional solution method and characterized by infrared, UV–Vis and single-crystal X-ray diffraction analyses. Thermal analysis was performed to study their thermal stability. The atomic arrangement in compound (1) can be described as inorganic layers built by [Mo8O26]4?, pyrrolidinium cations are embedded into layers. The fascinating structural feature of compound (2) is that the glycine molecules are bounded to two edge-sharing Mo centers via their carboxylate functionality leading to functionalized heteropolymolybdate [AsIIIMo6O21(O2CCH2NH3)3]3?, extensive net hydrogen bonds between cations and anions contribute to the crystal packing. The electrochemical behavior of compound (2) has been studied.  相似文献   
46.
The reversible thermoelastic γ-α′ martensitic transformations under load in new single-crystal ferromagnetic Fe-28%Ni-17%Co-11.5%Al-2.5%Ti (at %) alloy have been studied. It is shown for the first time that precipitation of dispersed particles of the γ′ phase during aging for 7 h at 973 K induces the shape-memory effect and superelasticity in [001] single crystals of Fe-Ni-Co-Al-Ti alloy upon tensile strain. Superelasticity ?SE = 4.5–6% manifests itself in the temperature range T = 183–333 K.  相似文献   
47.
In this study, extra virgin olive oil (EVOO) was mixed with sesame seed oil (SSO) at different concentrations (100:0, 90:10, 80:20, 70:30 and 60:40 w/w) and stored for 90 days at room conditions. To see the effect of mixing level and storage period, a combined design having two mixtures (EVOO and SSO) and one process factor (storage period) was used. Main oxidation parameters (free fatty acid content, refractive index, peroxide value and p-anisidine value) and major fatty acid composition of the samples were characterized. It was observed that EVOO is quite sensitive to oxidation compared to SSO and increase of SSO in the blended oil samples decreased the oxidation of the product during storage. Major fatty acids were palmitic, oleic and linoleic acids. Addition of SSO caused a significantly change in the fatty acid composition. The results showed that EVOO could be stored for longer time by mixing of SSO having strong antioxidant activity.  相似文献   
48.
Kara  Memduh  Ak  Safa  Uyaner  Mesut  Gunoz  Alper  Kepir  Yusuf 《Applied Composite Materials》2021,28(5):1567-1587

Chemical transmission lines, petroleum and natural gas lines, pressure vessels, and pipes used in thermal facilities are expected to maintain their mechanical properties for many years without being damaged and not to be corroded in working conditions. The composite materials are the right candidate for these harsh conditions due to their superior properties. Reinforcement of nanoadditives to composite materials improves both the mechanical properties and the resistance to environmental conditions, thereby increasing the lifetime. In this study, multi-walled carbon nanotube (MWCNT) reinforced [±?55°] carbon fiber/epoxy composite pipes produced with filament wound method were used. It was hydrothermally aged in 80 °C distilled water for 1, 2, 3 weeks in order to examine the effect of environmental conditions. In order to investigate its resistance against loads that may occur in working conditions, ring tensile tests (ASTM D 2290–16 procedure A), and low-velocity impact tests at 5, 10, 15 J, energy levels were carried out. The effect of hydrothermal aging on neat and MWCNT added epoxy composite had been examined by considering the aging period. Consequently, the impact resistance of neat and MWCNT added samples decreased with the aging process. Besides, tangential tensile strength loss was 17% in MWCNT reinforced sample and 13% in the neat sample.

  相似文献   
49.
Magnetic shape memory alloys (MSMAs) have recently been developed into a new class of functional materials that are capable of magnetic‐field‐induced actuation, mechanical sensing, magnetic refrigeration, and energy harvesting. In the present work, the magnetic &!hyphen;field‐induced martensitic phase transformation (FIPT) in Ni45Mn36.5Co5In13.5 MSMA single crystals is characterized as a new actuation mechanism with potential to result in ultra‐high actuation work outputs. The effects of the applied magnetic field on the transformation temperatures, magnetization, and superelastic response are investigated. The magnetic work output of NiMnCoIn alloys is determined to be more than 1 MJ m?3 per Tesla, which is one order of magnitude higher than that of the most well‐known MSMAs, i.e., NiMnGa alloys. In addition, the work output of NiMnCoIn alloys is orientation independent, potentially surpassing the need for single crystals, and not limited by a saturation magnetic field, as opposed to NiMnGa MSMAs. Experimental and theoretical transformation strains and magnetostress levels are determined as a function of crystal orientation. It is found that [111]‐oriented crystals can demonstrate a magnetostress level of 140 MPa T?1 with 1.2% axial strain under compression. These field‐induced stress and strain levels are significantly higher than those from existing piezoelectric and magnetostrictive actuators. A thermodynamical framework is introduced to comprehend the magnetic energy contributions during FIPT. The present work reveals that the magnetic FIPT mechanism is promising for magnetic actuation applications and provides new opportunities for applications requiring high actuation work‐outputs with relatively large actuation frequencies. One potential issue is the requirement for relatively high critical magnetic fields and field intervals (1.5–3 T) for the onset of FIPT and for reversible FIPT, respectively.  相似文献   
50.
In the present study a low-cost waste biomass derived from canned food plant, was tested for its ability to remove reactive textile dye from aqueous solutions. The batch biosorption experiments were carried out at various pH, biosorbent dosage, contact time and temperature. Optimum decolorization was observed at pH 2.0 and 1.6 g dm− 3 of biomass dosage within 20 min. The first-order and the pseudo-second-order kinetics were investigated for the biosorption system. The applicability of the Langmuir and Freundlich isotherm models was examined. The thermodynamic parameters for the biosorption were also calculated. The experimental results in this study indicated that this low-cost biomaterial was an attractive candidate for the removal of textile dye Reactive Red 198 (RR198) from aqueous solutions.  相似文献   
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