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排序方式: 共有124条查询结果,搜索用时 15 毫秒
51.
Christian J. Wijaya Suryadi Ismadji Hakun W. Aparamarta Setiyo Gunawan 《Molecules (Basel, Switzerland)》2021,26(15)
Due to its excellent characteristics, zeolitic imidazole framework-L (ZIF-L) is widely used in various applications, such as drug delivery, wastewater treatments and energy storage. In the synthesis of ZIF-L, the molar ratio of ligand to metal, the reaction time and the temperature are essential parameters to produce excellent ZIF-L. In this work, ZIF-L was synthesized using a facile and green synthesis method. It was statistically investigated and optimized to obtain the best operating conditions. The optimization was carried out toward the amount of adsorbed crystal violet (CV) dye () as the response in the statistics. The optimal ZIF-L was obtained using a molar ratio of ligand to metal of 8.2220 for 97 min at 29 °C, where the value of the CV adsorption onto this optimal ZIF-L reached 823.02 mg/g. The obtained ZIF-L was characterized using SEM, XRD, FTIR and TGA analyses to ensure its excellent characteristics. 相似文献
52.
We propose the use of soft feedback estimates for the PIC detector in aDS-CDMA system with FEC. The soft estimates are computed by the a posterioriof the log-MAP decoder. We compare this method with the conventional methodof using tentative hard decisions to perform interference cancellation at eachstage. Simulations under AWGN and multipath asynchronous channels areperformed for comparison. We supply a suitable a posteriori for the log-MAPdecoder, and obtain a suitable soft feedback from the decoder. 相似文献
53.
A method for the determination of lorazepam in rat brain is described using liquid/liquid and solid-phase extraction, followed by high performance liquid chromatography. After addition of chlordiazepoxide as the internal standard, 100 mg brain tissue was homogenized and incubated with alkaline protease. Lorazepam and chlordiazepoxide were extracted three times with toluene. After treatment through a C18-Bond Elut column, lorazepam and chlordiazepoxide were analyzed isocratically on a reversed-phase column with a mobile phase consisting of methanol +0.025 M sodium phosphate buffer (66:34, v/v). The eluted drugs were monitored by their absorption at 240 nm. The sensitivity limit of this method was 10 ng of lorazepam per 100 mg of brain tissue sample. The standard curve was linear over the range of 20 to 200 ng lorazepam. The coefficient of variation for day-to-day precision established by 21 replicate analyses was 4.5 to 13.6%. 相似文献
54.
JPC – Journal of Planar Chromatography – Modern TLC - A simple and rapid densitometric method has been developed for determination of betamethasone dipropionate and salicylic acid in... 相似文献
55.
Gunawan RC Choban ER Conour JE Silvestre J Schook LB Gaskins HR Leckband DE Kenis PJ 《Langmuir : the ACS journal of surfaces and colloids》2005,21(7):3061-3068
This work describes the use of microfluidic tools to generate covalently immobilized counter gradients of extracellular matrix (ECM) proteins laminin and collagen I. Using these platforms, we demonstrate control of the expression levels of two proteins linked to cell cycle progression by virtue of the spatial location of cells on the gradients, and hence by the local ECM environments in these devices. In contrast to physisorbed gradients, covalently immobilized protein patterns preserved the gradient fidelity, making long term cell studies feasible. This method of precisely controlling local cell environments is simple and broadly portable to other cell types and to other ECM proteins or soluble factors. Our approach promises to enable new investigations in cell biology that will contribute to the establishment of biological design rules for controlling cell growth, differentiation, and function. 相似文献
56.
JPC – Journal of Planar Chromatography – Modern TLC - A simple and rapid high-performance thin-layer chromatography (HPTLC) densitometric method has been developed for the determination... 相似文献
57.
Chunping Chen Poernomo Gunawan Xiong Wen Lou Rong Xu 《Advanced functional materials》2012,22(4):780-787
Simple and facile processes to produce silver nanoparticles deposited layered double hydroxide (Ag‐LDH) coatings are reported. High quality nanoporous LDH coatings are obtained under hydrothermal conditions via an improved in situ growth method by immersing the substrates in LDH suspensions after removal of free electrolytes. Different types of substrates including metal, ceramics, and glass with planar and non‐planar surfaces can all be coated with the oriented LDH films with strong adhesion. The pore size can be easily tuned by changing the metal:NaOH ratio during the precipiation process of LDH precursors. In the presence of LDH coatings, silver ions can be readily reduced to metallic silver nanoparticles (Ag NPs) in aqueous solutions. The resulting Ag NPs are incorporated evenly on LDH surface. The Ag‐LDH coating exhibits excellent and durable antimicrobial activities against both Gram‐negative (E. Coli and P. Aeruginosa) and Gram‐positive (B. Subtilis and S. Aureus) bacteria. Even at the 4th recycled use, more than 99% of all types of bacteria can be killed. Moreover, the Ag‐LDH coating can also effectively inhibit the bacterial growth and prevent the biofilm formation in the nutrient solutions. These newly designed Ag‐LDH coatings may offer a promising antimicrobial solution for clinical and environmental applications. 相似文献
58.
She Z Niu D Chen L Gunawan MA Shanja X Hersh WH Chen Y 《The Journal of organic chemistry》2012,77(7):3627-3633
A palladium-catalyzed, cascade 5-endo-dig cyclization-alkenylation synthesis of isoxazoles has been developed. The addition of 1 equiv of n-Bu(4)NBr significantly increases the yield of the desired 4-alkenyl-3,4,5-trisubstituted isoxazoles. A variety of trisubstituted isoxazoles are prepared in moderate to excellent yields. One example of the synthesis of a naphthoisoxazole is reported by a cascade cyclization-alkenylation-Heck reaction. 相似文献
59.
The design of coded frequency and phase modulation (FPM) with lower modulation index for fading channels is discussed. An asymmetric constellation is introduced to improve its performance. The proposed trellis coded modulation scheme is particularly advantageous in Rician fading channels with less severe fading conditions 相似文献
60.
Yoshihiro Sawano Denny Ivanal Hakim Hendra Gunawan 《Mathematische Nachrichten》2015,288(14-15):1741-1775
In the present paper, we consider the non‐smooth atomic decomposition of generalized Orlicz‐Morrey spaces. The result will be sharper than the existing results. As an application, we consider the boundedness of the bilinear operator, which is called the Olsen inequality nowadays. To obtain a sharp norm estimate, we first investigate their predual space, which is even new, and we make full advantage of the vector‐valued inequality for the Hardy‐Littlewood maximal operator. 相似文献