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991.
The nitrogen solubility index of proteins from Spirulina platensis as a function of pH in the range of 1 to 12 has been determined both in water and different concentrations of sodium chloride using the spray dried samples. Solubility characteristics show maximum solubility in the pH range of 8 to 10 in water and pH 6.0 ± 0.5 in 0.5 M sodium chloride. The ultraviolet and visible spectra have maxima at 285 and 620 nm, respectively. Fluorescence emission spectrum shows a maximum emission at 340 nm arising from tryptophanyl groups. The sedimentation velocity experiment shows two major fractions with sedimentation coefficient of 2.8 and 4.9 S. The functional properties of the protein are determined using the spray-dried sample. The result for water absorption (292 g/100 g), fat absorption (56 g/100 g), foaming and emulsion properties were determined and compared with egg protein as standard. An attempt is made to correlate the changes occurring as a result of spray drying of the functional properties to the physico-chemical properties of the protein in solution. 相似文献
992.
993.
994.
Sinter-Forging Characteristics of fine-Grained Zirconia 总被引:1,自引:0,他引:1
Powder preforms of zirconia, containing 2.85 mol% yttria, were sinter-forged in simple uniaxial compression at 1400°C by applying constant displacement rates to the specimens. Shear and densification strains and the uniaxial stress were measured as a function of time. In contrast with alumina and silicon nitride, zirconia appears to densify by a dislocation mechanism. As a consequence, the densification rate is linked to the applied strain rather than to the applied hydrostatic pressure; the powder compact requires a critical amount of compressive strain to consolidate to full density, irrespective of the strain rate or the stress at which that strain is applied. 相似文献
995.
We present a procedure for proving inductive theorems which is based on explicit induction, yet supports mutual induction. Mutual induction allows the postulation of lemmas whose proofs use the theorems ex hypothesi while the theorems themselves use the lemmas. This feature has always been supported by induction procedures based on Knuth-Bendix
completion, but these procedures are limited by the use of rewriting (or rewriting-like) inferences. Our procedure avoids
this limitation by making explicit the implicit induction realized by these procedures. As a result, arbitrary deduction mechanisms
can be used while still allowing mutual induction.
A preliminary version of this paper appeared in the proceedings of the 12th Conference on Automated Deduction, A. Bundy, editor.
This author was supported by a grant from the Ministère des Affaires Etrangères, France. 相似文献
996.
997.
DK Das S Bhambhani N Kumar KL Chachra S Prakash RK Gupta RP Tripathi 《Canadian Metallurgical Quarterly》1995,16(2):101-109
The study includes 61 cases which were subjected to ultrasound (US) guided fine needle aspiration cytology (FNAC) to find out the utility of this technique in the diagnosis of pancreatic lesions. Age of the patients ranged from 23 to 85 years with a median of 50 years. Male to female ratio was 36:25. One or more clinical diagnoses were offered in 16 and in 9 of these, the disease was related to pancreas. Subsequent to US, the lesions were localized to pancreas in 57 and the nature of pathology in the pancreatic lesion could be diagnosed in 31. By FNAC, 31 cases (50.8%) were diagnosed to have pancreatic malignancy which included adenocarcinoma (23 cases), papillary cystic tumour (1), muco-epidermoid carcinoma (1), acinic cell carcinoma (1), islet cell tumor (1), and non Hodgkin lymphoma (4). FNAC of liver in 2 cases and retroperitoneal lymph node in a case of pancreatic adenocarcinoma revealed metastasis. During follow up, 1 case of non Hodgkin's lymphoma showed CSF involvement. Three cases (4.9%) were suspected to have epithelial malignancy of which one was confirmed as an adenocarcinoma following surgery and histology. Four (6.6%) were benign lesions which included nonspecific inflammation (2 cases), tuberculous pancreatitis (1) and pseudopancreatic cyst (1). The remaining 23 cases (37.7%) had normal or inadequate cytology. Of these, FNAC of liver showed metastasis in 2 cases and one case each were diagnosed as adenocarcinoma and pseudopancreatic cyst respectively following surgery. None of the patients had any complication following FNAC. We recommend US guided FNAC to be routinely used for diagnosis of pancreatic lesion. 相似文献
998.
Sathyanarayana M. Upadrashta Pruthvipathy R. Katikaneni Gregory A. Hileman Prakash R. Keshary 《Drug development and industrial pharmacy》1993,19(4):449-460
Controlled release erodible matrix tablets were manufactured by a simple, direct compression process using ethylcellulose alone as the matrix former. Each of four different viscosity grades of ethylcellulose (10, 20, 45 and 100 cp) was dry mixed with either indomethacin or theophylline and a small amount of lubricant, then directly compressed into tablets. In initial trials, compression force was held constant, resulting in tablets of varying hardness. In a second study, the compression force was varied to produce tablets of equal hardness. Lower viscosity grades of ethylcellulose were more compressible than higher viscosity grades, allowing production of harder tablets for a given drug. Harder tablets resulted in controlled release of the drug over a longer time period. Dissolution studies indicated that tablet hardness is more important in determining dissolution rate than is the polymer viscosity grade. A mathematical model combining diffusion and erosion mechanisms was developed to describe drug release. Improved r2 values over pure diffusion, erosion and diffusion/relaxation models were obtained. Examination of residuals indicated that the derived composite model was more appropriate for the data 相似文献
999.
1000.
Ramamoorthy C.V. Usuda Y. Prakash A. Tsai W.T. 《IEEE transactions on pattern analysis and machine intelligence》1990,16(11):1225-1234
The evolution support environment (ESE) system, which provides a framework for capturing and making available semantic information about software components of an evolving software system, is described. The goal in the design of the ESE system was to provide integrated support for management of software architecture configuration, life-cycle configuration, and version control. Software architecture configuration management allows tracking of interconnections among software components that make up a system. Life-cycle management allows traceability among specifications, design, code, and test cases during software development. Adding version control allows specific versions of software objects and their associated objects, such as specifications and test cases, to be retrieved. The authors' experience with the use of the system is discussed 相似文献