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21.
Caillau Jean-Baptiste Djema Walid Gouzé Jean-Luc Maslovskaya Sofya Pomet Jean-Baptiste 《Journal of Optimization Theory and Applications》2022,194(2):375-407
Journal of Optimization Theory and Applications - We consider the problem of maximization of metabolite production in bacterial cells formulated as a dynamical optimal control problem (DOCP).... 相似文献
22.
W. A. Farooq S. M. Ali Walid Tawfik Amanullah Fatehmulla M. Aslam A. S. Al-Dwayyan M. S. AlSalhi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(13):2446-2450
ZnO Nano powders were prepared by co-precipitation method which includes post-oxidation and annealing in air. Influence of laser irradiation was carried out using 355 nm laser on the physical properties of ZnO nanoparticles. SEM studies reveal agglomeration of grains resulting into enlargement and deformation of the nanoparticles. XRD pattern exhibited decrease in FWHM which is a clear evidence of the increase in crystallite size due to laser irradiation. Optical properties showed decrease in the band gap of the laser irradiated Nano powders. The observed results indicated the UV laser irradiation increases the ZnO nanoparticles crystallinity that affects the optical properties of the ZnO. 相似文献
23.
A simple convenient protocol for the synthesis of diethyl α,α-diaryl methylphosphonate derivatives 5a-f, 6b-f, 7a-f and 8a-f, diethyl α-alkenyl α-aryl methylphosphonates 9a-d and 10a-d and α-(oxoalkyl) α-aryl methylphosphonate 11a-d and 12a-d is described. Trichloroacetimidates 3a-d were treated with activated arenes, styrene, allyltrimethylsilane or silylenol ethers C-nucleophiles in the presence TMSOTf to afford the desired products in good yields and short reaction time. 相似文献
24.
25.
M. Walid Qoronfleh 《Applied biochemistry and biotechnology》1999,80(2):107-120
A central problem in aerobic growth of any culture is the maintenance of dissolved oxygen concentration (DOC) above growth-limiting
levels especially in high-cell density fermentations that are usually of the fed-batch type. Fermentor studies have been conducted
to determine the influence of DOC on the production of heterologous proteins in Escherichia coli. The results demonstrated that there is a significant degree of product-to-product variation in the response of heterologous
protein accumulation to DOC. For translational fusions of the human immunodeficiency virus-1 (HIV-1) proteins p24Gag and Env41,
the imposition of a dissolved oxygen (DO) limitation resulted in 100 and 15% increases in the respective product yields. On
the other hand, the imposition of a DO limitation had no effect on the production of a similar translational fusion of the
HIV-1 protein p55Gag, and a large negative effect on the production of an influenza protein (C13). The stimulatory effects
of DOC on p24Gag production were investigated further. The results of my studies suggested that the stimulatory effect observed
at reduced agitation rates on p24Gag accumulation was owing to an oxygen effect and not a shear effect. Furthermore, the results
of my investigations indicated that the effect a DOC had on the production of p24Gag was strongly influenced by the cell density
at which the culture was induced. 相似文献
26.
Takashi Kashiwagi Eric Grulke Jenny Hilding Richard Harris Walid Awad Jack Douglas 《Macromolecular rapid communications》2002,23(13):761-765
Nanocomposites based on poly(propylene) and multi‐wall carbon nanotubes (up to 2 vol.‐%) were melt blended, yielding a good dispersion of nanotubes without using any organic treatment or additional additives. Carbon nanotubes are found to significantly enhance the thermal stability of poly(propylene) in nitrogen at high temperatures. Specifically, the nanotube additive greatly reduced the heat release rate of poly(propylene). They are found to be at least as effective a flame‐retardant as clay/poly(propylene) nanocomposites. 相似文献
27.
Walid Rekik Houcine Naïli Tahar Mhiri 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):i50-i52
Potassium gadolinium polyphosphate, KGd(PO3)4, was synthesized using the flux method. The atomic arrangement consists of an infinite long‐chain polyphosphate organization. Two types of chains, with a period of eight PO4 tetrahedra, run along the [101] direction. The Gd atoms have an eightfold coordination, while the K atoms have nine O‐atom neighbours. 相似文献
28.
Mohamed Fathi El-Shahat Hisham Mohamed Kamal Reda Abd El-Gawad Ghazall Walid Mohamed Morsy 《无机化学学报》2016,32(8):1427-1433
利用三异辛胺(TOA)纯化Gattar小型试验工厂的高浓度铀溶液(洗脱液的铀浓度7 g·L-1),研究了脉冲萃取柱的性能。利用实验室级脉冲萃取柱进行了实验室规模的溶剂萃取实验和后续实验。结果表明,在室温、pH=1和有机相与水相的比例(VO/VA)约为1.8:1时,加入二(2-乙基己基)磷酸(D2EHPA)使其与TOA的比例(VD2EHPA/VTOA)为2:3,可使萃取克服Cl-的抑制效应,提高效率。将结论用于考察试验工厂级萃取柱的流体力学和传质性能,结果表明用脉冲萃取柱萃取铀可以达到97%的萃取效率,具有可行性。 相似文献
29.
Saraya Roshdy E. Hassan Yasser F. Eltukhi Walid E. Salman Baher I. 《Journal of fluorescence》2022,32(5):1725-1732
Journal of Fluorescence - Vonoprazan (VON) has been approved recently via US-FDA in 2015 as the first in class of potassium competitive acid blocker group. VON is used for management of... 相似文献
30.
Walid F. Nasrallah Raymond E. Levitt 《Computational & Mathematical Organization Theory》2001,7(2):113-144
We present a general model of a network of interacting individuals, each of whom derives a known, real-valued benefit from each possible dyadic interaction. The model views interactions as knowledge-transfer exchanges that add value to the organization. We use this model to derive interaction patterns within an organization. We assume that the value of dyadic interaction benefits is distributed as a randomly permuted geometric series. Moreover, interactions only add value when a large enough waiting period is observed between interaction attempts. We show that an organization optimized for knowledge transfer has a distribution of interaction frequencies which correlates well with observations. Organizations of differing sizes can have similar optimal structures as long they have similar normalized levels of interdependence between interactions, and distribution of interaction benefit values. This research has implications for the design of communication infrastructure in a growing organization, as well as for the predictive value of modeling organizations at different scales. 相似文献