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61.
Bubble temperatures at 95 kPa over the entire composition range are measured for the five binary systems formed by 1,2-dimethylbenzene with 2-propanol, 1-butanol, 2-butanol, 2- methylpropan-1-ol, and 2-methylpropan- 2-ol. A Swietoslawski - type ebulliometer was used for the measurements. The composition versus temperature measurements are well represented by the Wilson model. 相似文献
62.
Xiang Jim; Sha Yuhua; Prasad Lata; Delbaere Louis T.J. 《Protein engineering, design & selection : PEDS》1996,9(6):539-543
Structural analysis derived from the crystallographic studyof the chimeric B72.3 antibody illustrated some major atomicinteractions between complementarity determining region (CDR)residues. For example, hydrogen bonds are formed between H35/H95,L50/H97, H53/H55 and H96/L96 respectively. These CDR residuesmay play important roles in the B72.3TAG72 (antibody-antigen)interaction either by direct interaction with the TAG72 antigenor by maintaining a CDR loop conformation through atomic interactionsbetween CDR residues. In order to confirm these assumptions,we altered these CDR residues by site-directed mutagenesis anddetermined binding affinities of these mutant chimeric antibodiesfor the TAG72 antigen in a solid-phase radioimmunoassay. Wefound that H55, H95, H97 and L96 are important CDR residuesfor the B72.3TAG72 interaction. Single amino acid substitutionsof aspartic acid and serine by alanine at H55 of CDR2 and atH95 of CDR3 respectively and of tyrosine by phenylalanine atH97 and L96 of CDR3, significantly reduced the binding affinityfor the TAG72 antigen by 20-, 8-, 16- and 45-fold respectively.Therefore, this study reveals some of the requirements for maintainingthe integrity of the B72.3 antibody combining sites. 相似文献
63.
Ranjit Prasad Vanja Pasanovic‐Zujo Rahul K. Gupta Ferenc Cser Sati N. Bhattacharya 《Polymer Engineering and Science》2004,44(7):1220-1230
Shear and extensional rheological measurements were conducted in conjunction with laser light scattering (LLS) on ethylene‐vinyl acetate copolymer (EVA) nanocomposites. The materials were prepared by melt‐mixing EVA and commercially acquired layered silicates. Wide Angle X‐Ray Scattering (WAXS) was used to ascertain the degree of layer swelling. This could be attributed to the intercalation of polymer chains into the interlayer of the silicates. The nanocomposites prepared were determined to be predominantly intercalated in nature. In shear rheological tests, the nanocomposites exhibited an increase in viscoelastic properties compared to the pure EVA. The extent of this property enhancement was not as pronounced as had been reported in many instances with respect to other polymer nanocomposites. This could be attributed to the absence of a network structure normally observed in an exfoliated system. The extensional rheological tests showed an increase in extensional flow properties. This was confirmed by the LLS, which indicated that the filled systems had higher deformability than the unfilled one. Polym. Eng. Sci. 44:1220–1230, 2004. © 2004 Society of Plastics Engineers. 相似文献
64.
This paper presents a segment-based probabilistic approach to robustly recognize continuous sign language sentences. The recognition strategy is based on a two-layer conditional random field (CRF) model, where the lower layer processes the component channels and provides outputs to the upper layer for sign recognition. The continuously signed sentences are first segmented, and the sub-segments are labeled SIGN or ME (movement epenthesis) by a Bayesian network (BN) which fuses the outputs of independent CRF and support vector machine (SVM) classifiers. The sub-segments labeled as ME are discarded and the remaining SIGN sub-segments are merged and recognized by the two-layer CRF classifier; for this we have proposed a new algorithm based on the semi-Markov CRF decoding scheme. With eight signers, we obtained a recall rate of 95.7% and a precision of 96.6% for unseen samples from seen signers, and a recall rate of 86.6% and a precision of 89.9% for unseen signers. 相似文献
65.
Kinetics of alkaline hydrolysis of mica-acrylonitrile graft copolymers was studied. The dependence of alkali concentration and the time of hydrolysis on the degree of saponification was determined. Chemical and spectroscopical techniques were used to determine the mechanism of hydrolysis. 相似文献
66.
Narsimha Parvatikar Shilpa Jain C. M. Kanamadi B. K. Chougule S. V. Bhoraskar M. V. N. Ambika Prasad 《应用聚合物科学杂志》2007,103(2):653-658
Polyaniline/cobalt oxide composites were synthesized by an in situ chemical polymerization method with ammonium persulfate as an oxidizing agent. This was a single‐step polymerization process for the direct synthesis of the emeraldine salt phase of the polymer. The polymers were characterized with X‐ray diffraction, scanning electron microscopy, and Fourier transform infrared spectral analysis. The formation of mixed phases of the polymer together with the conducting emeraldine salt phase was confirmed by spectroscopic techniques. High‐temperature conductivity measurements showed thermally activated behavior. A change in the resistance was observed with respect to the relative humidity when the pellets were exposed to a wide humidity range of 10–95%. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 653–658, 2007 相似文献
67.
Sadanandam Manchala V. Kamakshi Prasad V. Janaki 《International Journal of Speech Technology》2014,17(2):99-105
In this work, we have proposed new feature vectors for spoken language identification (LID) system. The Mel frequency cepstral coefficients (MFCC) and formant frequencies derived using short-time window speech signal. Formant frequencies are extracted from linear prediction (LP) analysis of speech signal. Using these two kind of features of speech signal, new feature vectors are derived using cluster based computation. A GMM based classifier has been designed using these new feature vectors. The language specific apriori knowledge is applied on the recognition output. The experiments are carried out on OGI database and LID recognition performance is improved. 相似文献
68.
This paper investigates the ability of a shear wave reflection (WR) method to monitor microstructural changes of Portland cement mortar during hydration. The wave reflection method measures the reflection loss of shear waves at an interface between a steel plate and mortar. Mortars with water/cement ratios of 0.35, 0.5 and 0.6 were tested at isothermal curing conditions of 25 °C. The numerical model HYMOSTRUC3D was used to simulate the evolution of microstructural properties of the cement paste phase of the tested mortars. The parameters obtained from the simulations were the volume fraction of the total and connected solid phase and the specific contact area of the hydrated cement particles. The investigations have shown that the wave reflection measurements are governed primarily by the degree of the inter-particle bonding of the cement particles as calculated from the specific contact area of a simulated microstructure. 相似文献
69.
The effect of ozone on Aspergillus niger causing black rot disease in onion was studied in culture. Ozone induced the spore germination in all treatments and few spores showed rapid swelling, resulting in the production of 2-3 germ tubes per spore compared to control. Although all the ozone treated spores germinated, all of them did not produce uniform colony morphology. Some colonies which developed from ozone treated spores failed to produce spores and such colonies appeared as grey patches of mycelia without spores amidst surrounding black sporulating colonies. Further work is in progress to study the mechanism involved in formation of sterile mycelia by ozone. 相似文献
70.
An unsteady state heat conduction model with a convective boundary condition is proposed for the drying of low-rank, high-porosity coals, such as lignites, during fluidized-bed combustion. The drying front is assumed to be the receding surface of a wet core. The solution technique for this moving boundary problem is based on the heat balance integral approach with immobilization of the moving boundary by a change in space variable. The governing cubic equation describing the drying curve in dimensionless form may be solved easily by the Newton—Raphson method. The model predictions are compared with experimental data for Mississippi lignite with excellent agreement. A correlation for estimation of total drying time is proposed. The temperature profiles obtained may be used for the study of the coupled drying and devolatilization in fluidized-bed combustors. The profiles could also be of importance in the study of formation of fissures/cracks in lignites subjected to intense heating conditions encountered during fluidized-bed combustion. 相似文献