Normalizations for periodogram-based unit root tests

We explore a periodogram-based unit root test that is invariant to nonzero means and invariant to nuisance parameters in the error series. We present modifications to account for trends and deterministic seasonal components.     

聚(ε-己内酯)/苯乙烯-丙烯腈共聚物共混物的形态研究

本文研究了聚(ε-己内酯)(PCI/苯乙烯-丙烯腈共聚物(SAN)共混物的形态。采用差示扫描量热计(DSC)测量了PCL/SAN共混物中的PCL结晶度随着SAN含量的增加而下降;当SAN浓度达到60wt％。以上时,PCI的结晶度趋于零。通过偏光显微镜可以观察到在含高浓度PCI的共混物中,PCL是以球晶形式存在的。样品是由PCL球晶充满的,但是随着SAN含量的增加,PCL球晶半径减小,球晶结构逐渐变得不规整,而X-射线衍射测试了不同组成的PCL/SAN共混物中PCL的晶胞参数没有改变,说明SAN没有进入到PCL的晶胞内。以小角X-射线散射结果发现PCI片晶之间的距离随着SAN含量的增加而增大。以上说明SAN分子与没有结晶的PCL形成无定形相夹在PCL的片晶之间。     

Force constants in hydrogen-bonded crystals

Hydrogen bond stretching force constants in crystals of imidazole, urea and cyanuric acid are calculated using both a modified CNDO/2 method and a constrained least squares fitting of interatomic pair potentials to the lattice vibrations. Results show that the modified CNDO/2 method gives closer agreement with the experimentally derived force constants than the normal CNDO/2 parameterization.     

The USCI approach and elementary superposition for combinatorial enumeration

Summary The elementary superposition theorems are presented for enumerating chemical compounds that contain achiral and chiral ligands. Subduced cycle indices (SCI-CF), partial cycle indices (PCI-CF), and cycle indices (CI-CF) with chirality fittingness are defined by starting from unit subduced cycle indices with chirality fittingness (USCI-CF). All of these indices afford generating functions that are proved to be applicable to combinatorial enumeration. In addition, the concept of elementary superposition with and without chirality fittingness is proposed to provide the elementary superposition theorems. These theorems provide us with a new methodology of enumerating compounds, in which the numbers of isomers are obtained without relying on generating functions and are itemized with respect to molecular formulas (weights) and symmetries. The operation is defined on the basis of the elementary superposition. Thereby, we derive superposition theorems concerning the PCI-CFs and the CI-CFs. These are applicable to combinatorial enumeration.     

Application of stress induces ascorbate peroxidases of S. polyrhiza for green-synthesis Cu nanoparticles

The objective of this study was to assess the effects of stress on physiology/biochemical component of S. polyrhiza and its impact on CuNPs synthesis and bioethanol production. NaCl with RV5 provokes oxidative stress in S. polyrhiza and significantly increase MAD, Proline, H₂O₂, ROS, SOD and APX activity compare to control condition. Starch accumulation in S. polyrhiza was found 354% higher and correspond 4.4 times higher ethanol yield under stress condition compare to control. CuNPs were synthesized with an average size of 23–26 nm by purified fraction of APX having 37 KDa MW, 1.44 IU specific activity. Synthesized CuNPs were stable up to 15 consecutive cycles and potency against wide range of reactive dyes. The maximum remedial efficiency of synthesized CuNPs for COD and BOD was 55263.3 ± 3298.5 mg/m³min. and 30560.3 ± 1987.5 mg/m³min. respectively for RV5 wastewater. 0.072 mg/g of bioethanol was produced from the wet pulp remaining after nanoparticles synthesis. High efficiency of CuNPs and significant production of Ethanol, indicate that the feasibility for circular model for continuous industrial wastewater treatment.     

Pareto optimal design of layered bandgap materials with multiphase microstructures using evolutionary algorithms

An important characteristic of the periodic materials or structures is the existence of bandgap. This bandgap, which is dispersion-related, can be designed by controlling the materials layout within the periodic microstructures. In this paper, the topologies of periodic multiphase microstructures are optimized using a multiobjective genetic algorithm and two cases of studies are presented. The results show that 3-phase material can obtain quite better designs on the basis of fewer layers. This will be a reference for the design of phononic bandgap materials.     

Ultrasound induced green solvent extraction of oil from oleaginous seeds

Ultrasound-assisted extraction of rapeseed oil was investigated and compared with conventional extraction for energy efficiency, throughput time, extraction yield, cleanness, processing cost and product quality. A multivariate study enabled us to define optimal parameters (7.7 W/cm² for ultrasonic power intensity, 40 °C for processing temperature, and a solid/liquid ratio of 1/15) for ultrasound-assisted extraction of oil from oilseeds to maximize lipid yield while reducing solvent consumption and extraction time using response surface methodology (RSM) with a three-variable central composite design (CCD). A significant difference in oil quality was noted under the conditions of the initial ultrasound extraction, which was later avoided using ultrasound in the absence of oxygen. Three concepts of multistage cross-current extraction were investigated and compared: conventional multistage maceration, ultrasound-assisted maceration and a combination, to assess the positive impact of using ultrasound on the seed oil extraction process. The study concludes that ultrasound-assisted extraction of oil is likely to reduce both economic and ecological impacts of the process in the fat and oil industry.     

漆酚铝螯合聚合物的合成研究

本文报道漆酚与无水氯化铝反应合成漆酚铝螯合物的方法,并通过测定反应过程HCl析出量、产物含铝量,并用红外光谱、质谱,研究其结构特征。实验表明,部分螯合的漆酚铝螯合型高聚物涂料,具有优良的物理机械性能和优异的耐热性能。     

Improved performance analysis of Gigabit passive optical networks

Gigabit passive optical networks (GPON) provide a capacity boosts in both the total bandwidth and bandwidth efficiency through the use of larger variable-length packets in Passive Optical Networks technology. In this paper, we have described a purely-passive GPON compatible reach extender using distributed Raman amplification and reported the improved investigation through implementation of a square root module by a distance of 60 km at data rate of 2.5 Gbps. An efficient improvement in Q factor is achieved with square root module, which further helps in increasing the length of GPON.