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排序方式: 共有1886条查询结果,搜索用时 15 毫秒
71.
Prithvi Sai Nadh Garikiparthy Seung Chul Lee Hongbin Liu Srinivas Sahan Kolluri Iman Janghorban Esfahani Chang Kyoo Yoo 《Korean Journal of Chemical Engineering》2016,33(1):14-24
We developed several control algorithms and compare their control performances for controlling the total phosphorous (TP) concentration in wastewater treatment plant, which has strong influent disturbances and the disturbance effects should be removed while maintaining better effluent quality. An anaerobic - anoxic - oxic (AAO) process, which is a well-known advanced nutrient removal process, was selected as a case study, which is modeled with activated sludge model no. 2. Six control strategies for TP control with a polymer addition were implemented in AAO process and evaluated by the plant’s performance, where the costs of the dosed chemical were compared among the six controllers. The experimental work showed that the advanced control techniques with feedback, feedforward and feedratio controllers were able to control the TP concentration in the effluent, which must be less than 1.50 g P/m3 which is the legal limitation, while reducing the necessary chemical cost. The results showed that the best TP removal performance in the effluent TP removal could be achieved by advanced feedback controller with the tuned control parameters, which showed the best effluent quality and control performance index as well as the cheapest cost of chemical dosage among the six TP control strategies. 相似文献
72.
通过质子酸胶体处理,实现了碳化钛Ti3C2Tx的制备。此外,使用单壁碳纳米管(SWCNT)作为增强成分,提升了质子酸处理碳化钛(H-MXene)的机械性能——不仅保持了电磁屏蔽性能,而且将拉伸性能提升了近400%。结果表明,H-MXene和碳纳米管具有作为高机械性能电磁(EMI)屏蔽复合材料的潜力。 相似文献
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Encapsulation of organogels is a novel perspective in the field of controlled drug delivery. This study reports encapsulation of lanolin based organogels within alginate microparticles. The microparticles were prepared by emulsification/internal gelation method. Microscopic studies suggested spherical shape of the microparticles. Fourier transform infrared, X‐ray diffraction and thermal studies confirmed the presence of organogels within the microparticles. Organogels containing microparticles showed improved drug (e.g., salicylic acid and metronidazole) entrapment efficiency. The release of the drugs from the microparticles was dependent on the pH of the dissolution medium. The release was diffusion mediated. The drug loaded microparticles showed antimicrobial activity against E. coli and B. subtilis. The preliminary study suggested that the encapsulation of the organogels may help prolonging the release of the drugs and hence may be tried as vehicles for controlled drug delivery. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40910. 相似文献
75.
Gelatin‐carbohydrate phase‐separated hydrogels as bioactive carriers in vaginal delivery: Preparation and physical characterizations
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Vinay Kumar Singh Sai Sateesh Sagiri Kunal Pal Shankar M. Khade Dillip K. Pradhan Mrinal K. Bhattacharya 《应用聚合物科学杂志》2014,131(13)
The current study focuses on the alteration of properties of the gelatin hydrogels using polysaccharides (e.g., maltodextrin, dextran, and sodium carboxymethyl cellulose) for probable use in vaginal delivery of antimicrobials. The hydrogels were prepared by varying the proportions of gelatin and polysaccharides and were characterized by microscopy, mechanical testing, and impedance spectroscopy. Metronidazole (MZ), drug of choice for the treatment of bacterial vaginosis, was incorporated within the hydrogels. In vitro release studies of MZ from the hydrogels was studied in‐depth using modified Franz's diffusion cell. Antimicrobial efficiency of the MZ‐loaded hydrogels was tested against E. coli and B. subtilis. The results suggested that the incorporation of polysaccharides resulted in the phase‐separated hydrogels. The properties of the hydrogels was found be suitable for vaginal delivery. The drug release and antimicrobial efficiency from the hydrogels suggested that the developed hydrogels may be used for the delivery of antimicrobials in the vaginal lumen. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40445. 相似文献
76.
Tao Zhu Pingli Li Xiaowei Wang Wandian Yang Heying Chang Sai Ma 《Korean Journal of Chemical Engineering》2014,31(9):1624-1631
Dilute acid pretreatment of lignocellulosic material is one of the significant steps in a biorefinery. We used response surface methodology to determine the important factors of formic acid concentration (2%–6% wt%), treatment time (30–150 min), reaction temperature (120–160 °C), and liquid to solid ratio (3–11 mL/g) on dilute acid hydrolysis of corn cob to produce xylose. A xylose yield of 81.6% and selectivity of 15.1 g/g were achieved under the optimal conditions (5% acid concentration, 150 min, 135 °C, and 7 mL/g liquid to solid ratio). The addition of trivalent salts (FeCl3, Fe(NO3)3, and Fe2(SO4)3) to the reaction system enhanced the xylose yield but decreased selectivity. The FeCl3 concentration over 0.75 mol/L had a negative effect on xylose production. 相似文献
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许多机械传动部件如齿轮在加工的过程中需要严格的保证其加工精度,传统的检测齿轮精度的设备只能在齿轮加工完成后才能对齿轮的精度进行测量,无法在齿轮加工的过程中对齿轮的加工精度进行测量。本文设计了一种齿轮加工在线智能检测装置,能在齿轮加工的过程中对齿轮的轮廓数据进行采集,将机床工作台旋转坐标反馈数据与在线智能检测装置测量的数据进行同步,将检测获得的数据在极坐标下表示即为被加工齿轮齿面检测点的坐标,当被加工工件旋转一周,在线智能检测装置能够测得工件完整的横截面点云坐标。本装置可以有效地实现对加工过程中的齿轮进行测量,具有结构简单、操作快捷、安装方便等优点。 相似文献
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80.
Zhiqi Hao Sai Ma Lunping Liang Ting Feng Mengyuan Xiong Shangshu Lian Jingyan Zhu Yanjun Chen Lijun Meng Min Li 《International journal of molecular sciences》2022,23(7)
Drought and salinity stresses are significant abiotic factors that limit rice yield. Exploring the co-response mechanism to drought and salt stress will be conducive to future rice breeding. A total of 1748 drought and salt co-responsive genes were screened, most of which are enriched in plant hormone signal transduction, protein processing in the endoplasmic reticulum, and the MAPK signaling pathways. We performed gene-coding sequence haplotype (gcHap) network analysis on nine important genes out of the total amount, which showed significant differences between the Xian/indica and Geng/japonica population. These genes were combined with related pathways, resulting in an interesting mechanistic draft called the ‘gcHap-network pathway’. Meanwhile, we collected a lot of drought and salt breeding varieties, especially the introgression lines (ILs) with HHZ as the parent, which contained the above-mentioned nine genes. This might imply that these ILs have the potential to improve the tolerance to drought and salt. In this paper, we focus on the relationship of drought and salt co-response gene gcHaps and their related pathways using a novel angle. The haplotype network will be helpful to explore the desired haplotypes that can be implemented in haplotype-based breeding programs. 相似文献