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排序方式: 共有133条查询结果,搜索用时 475 毫秒
1.
Abdulaziz S. Alidi 《Applied Mathematical Modelling》1992,16(12):645-651
The improper handling and disposal of hazardous wastes cause threats to human health and the environment. One reason for the improper handling and disposal of these wastes is that not much consideration is usually given to the logistical aspects of hazardous waste systems. In this paper an integer goal programming model is developed that takes into consideration the multiple goals and needs of many groups involved in managing and planning hazardous waste systems. The model can easily be implemented and can be used to address many of the issues related to facility location, recycling, treatment, and disposal of hazardous wastes. 相似文献
2.
Ab initio calculations using the MP2/cc-pVTZ basis set do an excellent job of predicting the inversion barrier (247 vs. 232 cm−1) and dihedral angle (26°) of cyclopentene. DFT calculations also do an excellent job of predicting the vibrational frequencies of the d0, d1, d4, and d8 isotopomers. They have also allowed the reassignments of several of the vibrational frequencies. 相似文献
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6.
Vijayakumar Uppar Sandeep Chandrashekharappa Chandan Shivamallu Sushma P Shiva Prasad Kollur Joaquín Ortega-Castro Juan Frau Norma Flores-Holguín Atiyaparveen I. Basarikatti Mallikarjun Chougala Mrudula Mohan M Govindappa Banuprakash Jayadev Katharigatta N. Venugopala Belakatte P. Nandeshwarappa Ravindra Veerapur Abdulaziz A. Al-Kheraif Abdallah M. Elgorban Asad Syed Kiran K. Mudnakudu-Nagaraju Basavaraj Padmashali Daniel Glossman-Mitnik 《Molecules (Basel, Switzerland)》2021,26(9)
7.
I. Hashim O. Abdulaziz S. Momani 《Communications in Nonlinear Science & Numerical Simulation》2009,14(3):674-684
In this paper, the homotopy analysis method is applied to solve linear and nonlinear fractional initial-value problems (fIVPs). The fractional derivatives are described by Caputo’s sense. Exact and/or approximate analytical solutions of the fIVPs are obtained. The results of applying this procedure to the studied cases show the high accuracy and efficiency of the approach. 相似文献
8.
A method for inverting the Laplace transform is presented, using a finite series of the classical Legendre polynomials. The
method recovers a real valued function f(t) in a finite interval of the positive real axis when f(t) belongs to a certain
class
and requires the knowledge of its Laplace transform F(s) only at a finite number of discrete points on the real axis s>0.
The choice of these points will be carefully considered so as to improve the approximation error as well as to minimize the
number of steps needed in the evaluations. The method is tested on few examples, with particular emphasis on the estimation
of the error bounds involved. 相似文献
9.
Jing Qin Guohai Liang Bingxi Feng Gen Wang Na Wu Yonghui Deng Ahmed A. Elzatahry Abdulaziz Alghamdi Yongxi Zhao Jing Wei 《中国化学快报》2021,32(2):842-848
Plant polyphenol-based coordination polymers(CPs) with ultra-small particle size and tailorable compositions are highly desired in biomedical applicatio ns,but their synthesis is still challenging due to the sophisticated coordination assembly process and unavoidable self-oxidation polymerization of polyphenol. He rein,a general ligand covalent-modification mediated coordination assembly strategy is proposed for the synthesis of water-dispersible CPs with tunable metal species(e.g., Gd,Cu,Ni,Zn,Fe)and ultra-small diameter(8.6-37.8 nm) using nontoxic plant polyphenol(e.g..tannic acid,gallic acid) as a polymerizable ligand.Polyphenol molecules react with formaldehyde firstly,which can effectively retard the oxidation induced self-polymerization of polyphenol and lead to the formation of metal ions containing CPs colloidal nanoparticles.These ultrafine nanoparticles with stably chelated metal io ns are highly water dispersible and thus advantageous for bioimaging.As an example,ultra-small Gd contained CPs exhibit higher longitudinal relaxivity(r_1=25.5 L mmol ~1 s ~1) value with low r_2/r_1(1.19) than clinically used Magnevist(Gd-DTPA,r_1=3.7 L mmol ~1 s ~1).Due to the enhanced permeability and retention effect,they can be further used as a positive contrast agent for T_1-weighted MR imaging of tumour. 相似文献
10.
Mamadalieva NZ Janibekov AA Girault JP Lafont R 《Natural product communications》2010,5(10):1579-1582
Chemical investigations of Silene viridiflora (L.) yielded a new ecdysteroid, 20-hydroxyecdysone 20,22-monoacetonide-25-acetate (1), and a known ecdysteroid, 2-deoxypolypodine B-3-beta-D-glucoside (2). The elucidation of the chemical structures was established by 1D and 2D NMR experiments. 相似文献