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101.
We consider an integrated planning and scheduling problem motivated by the coal supply chains in Australia. The problem considers production planning of several independent mines. The mines need trains to complete delivery of coal by the arrival of ships at the terminal. The trains, on the other hand, are in limited supply and therefore the mines need to share this common resource. For this problem, we present a mixed integer programming formulation which minimises total weighted earliness, tardiness and operational costs. We also present a distributed algorithm based on the Lagrangian relaxation, which incorporates the volume and Wedelin algorithms. The strength of our distributed algorithm is demonstrated by an extensive computational experiment on several randomly generated instances.  相似文献   
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Alpha amylases are hydrolytic enzymes that are widespread in nature, being found in animals, microorganisms, and plants. These enzymes hydrolyze starch molecules into reducing sugars. Alpha amylases from microbial sources have several applications in industrial sectors. This enzyme is an effective target for the development of anti‐fungal agents. The binding affinity and enzyme inhibitory properties of 6‐gingerol toward alpha amylase have been determined. Molecular modeling and docking has been carried out, in order to get the molecular level interactions. Enzyme inhibition studies proved that 6‐gingerol is a competitive inhibitor of fungal alpha amylase. It was inferred that 6‐gingerol is a potent natural inhibitor of alpha amylase.  相似文献   
105.
Increased blood pressure and plasma cholesterol concentration are the major risk factors for cardiovascular diseases. We have previously shown that fermented milk products containing casein-derived bioactive tripeptides, isoleucine-proline-proline (Ile-Pro-Pro) and valine-proline-proline (Val-Pro-Pro) partly inhibit the blood pressure increase in spontaneously hypertensive rats (SHR). In the present study, we investigated the effect of bioactive tripeptide-containing fermented milk products (with or without plant sterols) on blood pressure and vascular function in salt-loaded type 2 diabetic Goto–Kakizaki (GK) rats after 8 weeks’ treatment. The development of blood pressure was attenuated in the groups receiving tripeptide-containing products (?10 to ?12 mmHg vs. the control product group, P < 0.01). Tripeptide-containing products enhanced the impaired endothelium-dependent relaxation of mesenteric arteries. Also the role of endothelium-derived hyperpolarizing factor (EDHF) was demonstrated. Interestingly, pretreatment of arterial rings with verapamil normalized the impaired endothelial function. Endothelium-independent relaxations were similar between the groups. Furthermore, tripeptides had positive effects on renin–angiotensin–aldosterone system.  相似文献   
106.
The paper reports synthesis of Ag-polyaniline nanocomposite and its evaluation as an active optical cladding on a planar optical waveguide (POW) as a humidity sensor with variable concentration of the composite. The nanocomposite is dispersed in acetonitrile, and spin coated on the planar waveguide to form a clad. The system shows response to humidity, when tested in the range of 20–92% relative humidity (RH). A prism film coupling is used to characterize the cladded waveguide. The maximum sensitivity is seen for 47% concentration of the nanocomposite in acetonitrile. The response and recovery of the sensor are 8 and 55 s respectively. The low hysteresis is exhibited by the sensor. The sensor has repeatability and reproducibility. Material characterization is done using Scanning Electron Micrograph (SEM), X-Ray Diffraction (XRD), Ultraviolet Spectroscopy (UV) and Fourier Transform Infrared Spectroscopy (FTIR).  相似文献   
107.
Anu Philip 《Vacuum》2010,85(3):368-372
An explanation for the possible mechanism of formation of alumina nanoparticles in Atomic Layer Deposition process of Alumina using Trimethyl aluminum (TMA) and water in a cold wall ALD chamber is given based on the physisorption of TMA and surface energy of alumina thin films. The sorption mechanism proposed is physisorption at the cold walls rather than the conventional chemisorption at the hot substrates as in the case of typical ALD. It is argued that when the surface energy of alumina is larger than the physorption energy, the newly forming film will try to reduce the surface area and assume spherical shape forming nano particles. Synthesized particles were characterized using XRD, SEM, HRTEM, SAED, FTIR and EDS. It was found that the particle size varied from ∼20 nm to 45 nm. The samples were identified as slightly aluminum rich alumina. The as prepared samples were amorphous whereas annealing at 1200 deg C made them crystalline. Dielectric studies of pelletized samples yielded a dielectric constant of 9.08 which agreed well with reported values.  相似文献   
108.
This article presents a hardware-efficient design of 2-bit ternary arithmetic logic unit (ALU) using carbon nanotube field-effect transistors (CNTFETs) for nanoelectronics. The proposed structure introduces a ternary adder–subtractor functional module to optimise ALU architecture. The full adder–subtractor (FAS) cell uses nearly 72% less transistors than conventional architecture, which contains separate ternary cells for addition as well as subtraction. The presented ALU also minimises ternary function expressions with utilisation of binary gates for optimisation at the circuit level, thus attaining a simple design. Hspice simulations results demonstrate that the ALU ternary circuits achieve great improvement in terms of power delay product with respect to their CMOS counterpart at 32 nm.  相似文献   
109.
The kinetics and mechanism of oxidative decolorisation of Eriochrome Black T (EBT) with sodium N‐chloro‐p‐toluenesulfonamide or Chloramine‐T (CAT), catalysed by osmium tetroxide [Os(VIII)] in alkaline medium and uncatalysed in acid medium, have been spectrophotometrically investigated at 303 K. The reaction exhibited a first‐order dependence of rate on [CAT]0 and [EBT]0 in both media, and also with respect to [H+]. The order with respect to [OH] and [Os(VIII)] was fractional. Activation parameters were deduced. It was observed that the uncatalysed decolorisation reaction was ca. eightfold faster in acid medium in comparison with alkaline medium, while the Os(VIII)‐catalysed reaction was ca. sevenfold faster than the uncatalysed reaction. Mechanisms and rate laws were determined. The chemical oxygen demand of Eriochrome Black T dye was also determined. Importantly, the developed oxidative decolorisation method is simple, efficient, inexpensive, requires less time, and is environmentally benign. Hence, it can be adapted for treating Eriochrome Black T present in industrial and laboratory wastewater.  相似文献   
110.
In scaled technologies with lower supply voltage, conventional Static Random Access Memory (SRAM) cell suffers from unsuccessful read & write operation due to high off state current in sub-threshold region at nanometre technologies. This work proposes new functional low-power designs of SRAM cells with 7, 8, 9 and 12 transistors which operate at only 0.4V power supply in sub-threshold operation at 45 nm technology. Stability analysis is carried out using static noise margins as well as N-curve cell stability metrics. For performance measurement, read/write access time and leakage power consumption in hold mode are analysed. The comparison with published designs shows that two new proposed designs namely M8T, MPT8T have 30% less leakage power consumption along with 2× read stability, 2× write ability, more than 60% faster read & write operation.  相似文献   
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