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排序方式: 共有776条查询结果,搜索用时 15 毫秒
51.
Rupsankar Chakrabarti & Badiveddy Madhusudana Rao 《International Journal of Food Science & Technology》2008,43(1):179-184
The annual inland fish production in India is 3.2 million tonnes and above. Aquaculture is around 80% of total inland fish production. The enhanced aquaculture production demands alternate processing methods for better utilisation of the farmed fish. Cirrhinus mrigala is one of the dominated species among cultured Indian major carps, but rated with lowest price. Fish meat with good gel‐forming capacity is a prerequisite in the production of fast‐moving fabricated analogue product. Cirrhinus mrigala had the highest gel strength, i.e. 435 gcm of its fresh meat in comparison with other carps. Apart from the highest protein and salt‐soluble protein nitrogen content in fresh C. mrigala meat, this article also reports that the presence of the darkest thick band of myosin heavy chain and actin in the polyacrylamide gel electrophoresis pattern of salt‐soluble extract of C. mrigala might be another possible reason for the highest gel strength in comparison with other carps. Cirrhinus mrigala contained white meat around 90%. This carp could be suitably used in the preparation of high‐valued fabricated analogue product. 相似文献
52.
A theoretical analysis of mass transfer effects in ethyl cellulose manufacture has been reported. This is the first model to describe a complex fluid–solid reaction in the presence of two immiscible liquids. The model derived here can be used to evaluate the dependency of the overall rate on different parameters incorporating the multiphase mass transfer effects. 相似文献
53.
Discovery of Quinoline‐Derived Trifluoromethyl Alcohols,Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model
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Prof. Dr. Vinoth Sittaramane Jihan Padgett Philip Salter Ashley Williams Shauntelle Luke Rebecca McCall Prof. Dr. Jonathan F. Arambula Vincent B. Graves Mark Blocker David Van Leuven Keturah Bowe Julia Heimberger Hannah C. Cade Supriya Immaneni Prof. Dr. Abid Shaikh 《ChemMedChem》2015,10(11):1802-1807
In this study the rational design, synthesis, and anticancer activity of quinoline‐derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp3‐C?H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4‐trifluoro‐3‐hydroxy‐3‐(quinolin‐2‐ylmethyl)butanoate ( 1 ), 2‐benzyl‐1,1,1‐trifluoro‐3‐(quinolin‐2‐yl)propan‐2‐ol ( 2 ), and trifluoro‐3‐(isoquinolin‐1‐yl)‐2‐(thiophen‐2‐yl)propan‐2‐ol ( 3 ). Compounds 2 and 3 were found to be more toxic than compound 1 ; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2 , with an LC50 value of 14.14 μm , has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents. 相似文献
54.
Anwesha Maity Dipul Kalita Tarun Kumar Kayal Tridip Goswami Omprakash Chakrabarti Himadri Sekhar Maiti Paruchuri Gangadhar Rao 《Ceramics International》2010,36(1):323-331
Synthesis of SiC ceramic from processed cellulosic bio-precursor was investigated. Bamboo (Bambusa tulda Roxb.) plants abundantly available in the Jorhat district of Assam, India, were selected for extraction of fibers following Kraft pulping method and bleached bamboo pulp fibers were suitably cast in the form of rectangular boards. Coir fibers available in the Alleppy district of Kerala, India, were initially digested with dilute alkali, mixed with cellulose acetate solution, air dried and then hot-pressed at 140 ± 5 °C under 2.0–2.5 MPa pressure to make rectangular boards. Well-characterized processed bio-precursors were pyrolysed at ~800 °C under flowing N2 atmosphere to prepare the bio-carbonaceous preforms (carbon templates) which showed nearly uniform shrinkages in all directions. Coir fiber composite board carbon showed lower pyrolytic weight loss (~66%), higher density (0.49 g cm?3), lower porosity (~58%) and narrower pore diameter (10 μm) compared to the cast bamboo pulp fiber board carbon. The carbon samples showed perfect retention of fibrous morphological features of hierarchically grown bio-structures. Ceramization of carbon templates could be done by reactive melt silicon infiltration into porous channels at ~1600 °C under vacuum. The final ceramics were adequately dense (%theoretical density > 99%), showed negligible linear dimensional changes (indicating net-dimension formation capability), presence of crystalline Si and SiC phases and duplex microstructure with complete preservation of fibrous architecture of plant bio-structure. The Si/SiC ceramic composite synthesized from coir fiber board gave room temperature 3-point flexural strength and Young's modulus values of 121 MPa and 276 GPa, respectively. Both the ceramic composites showed adequate oxidation resistance during heating at 1300 °C for 7 h in air. 相似文献
55.
Supriya Karmakar 《SILICON》2014,6(3):169-178
Quantum dot gate FETs (QDGFET) produce one intermediate state between two stable on and off states due to the change in the threshold voltage. A circuit model based on Berkeley Short-channel IGFET Model (BSIM) that accounts for this intermediate state is developed. Different ternary logics such as ternary logic inverter, MAX-MIN functions, multiplier, comparator, etc. can be implemented using QDGFETs. In this work the designs of ternary logic AND and OR gate based on QDGFET is introduced. Increased number of states in three state QDGFETs will increase the number of bit handling capability of this device and will help to handle more bits at a time with less circuit elements. 相似文献
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58.
Krishnendu Chatterjee Pallab Dasgupta P. P. Chakrabarti 《Journal of Automated Reasoning》2003,30(2):205-232
Temporal logics such as Computation Tree Logic (CTL) and Linear Temporal Logic (LTL) have become popular for specifying temporal properties over a wide variety of planning and verification problems. In this paper we work towards building a generalized framework for automated reasoning based on temporal logics. We present a powerful extension of CTL with first-order quantification over the set of reachable states for reasoning about extremal properties of weighted labeled transition systems in general. The proposed logic, which we call Weighted Quantified Computation Tree Logic (WQCTL), captures the essential elements common to the domain of planning and verification problems and can thereby be used as an effective specification language in both domains. We show that in spite of the rich, expressive power of the logic, we are able to evaluate WQCTL formulas in time polynomial in the size of the state space times the length of the formula. Wepresent experimental results on the WQCTL verifier. 相似文献
59.
Acesulfame-K, a sweetening agent, was evaluated in vivo for its genotoxic and clastogenic potentials. Swiss albino male mice were exposed to the compound by gavage. Bone marrow cells isolated from femora were analysed for chromosome aberrations. Doses of 15, 30, 60, 450, 1500 and 2250 mg of acesulfame-K/kg body weight induced a positive dose-dependent significant clastogenicity (trend test alpha < 0.05). These doses were within the no-toxic-effect levels (1.5-3 g/kg body weight in rats) reported by the Joint Expert Committee for Food Additives of the World Health Organization and the Food and Agriculture Organization of the United Nations. In view of the present significant in vivo mammalian genotoxicity data, acesulfame-K should be used with caution. 相似文献
60.
A.C. PatthakI. Bhattacharya A. Dasgupta Pallab DasguptaP.P. Chakrabarti 《Information Processing Letters》2002,82(3):123-129
Computation Tree Logic (CTL) is one of the most syntactically elegant and computationally attractive temporal logics for branching time model checking. In this paper, we observe that while CTL can be verified in time polynomial in the size of the state space times the length of the formula, there is a large set of reachability properties which cannot be expressed in CTL, but can still be verified in polynomial time. We present a powerful extension of CTL with first-order quantification over sets of reachable states. The extended logic, QCTL, preserves the syntactic elegance of CTL while enhancing its expressive power significantly. We show that QCTL model checking is PSPACE-complete in general, but has a rich fragment (containing CTL) which can be checked in polynomial time. We show that this fragment is significantly more expressive than CTL while preserving the syntactic beauty of CTL. 相似文献