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31.
Soft ice-cream samples were prepared with different proportions of cream and skimmed milk powder (SMP) and were examined for quality by physico-chemical parameters and sensory attributes. The specific proportions of cream and SMP were designed using the central composite rotatable design (CCRD). Response surface analysis indicated that sensory flavour, texture and overall acceptability (OAA) scores of soft ice-cream varied from 7.12 to 8.86, 6.66 to 8.03 and 6.90 to 8.45, respectively. The differences in the sensory scores for respective attributes were highly significant ( P ≤  0.01). The soft ice-cream containing a minimum level of 3.24% cream and 4.94% SMP resulted in a product having a minimum of 4.3% fat, 5.7% lactose and 33% total solids, with a minimum OAA score of 8. The derived mathematical second-order polynomial models against cream (X) and SMP (Y) were found to be adequate as coefficients of multiple determinants ( R 2) were more than 80% except for melting resistance.  相似文献   
32.
The gene encoding the stress-inducible member of human heat shock protein hsp70, was expressed in E. coli using the bacteriophage T7 RNA polymerase-based gene expression system. Recombinant hsp70 (R-hsp70) was purified from inclusion bodies after solubilization and refolding, using a combination of ATP-agarose affinity chromatography and ion-exchange chromatography. R-hsp70 was shown to be monomeric and free of its structurally similar E. coli counterpart, DnaK. In addition, R-hsp70 is functional as demonstrated by its ability to bind to peptides and to ATP. The availability of pure, correctly folded R-hsp70 in sufficient quantity will assist in the structural and functional characterization of hsp70. Furthermore, an understanding of the cytoprotective function of hsp70 and its role in immune responses during infections will be facilitated by the availability of pure R-hsp70.  相似文献   
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34.
This work obtains a correlation between the physical structure and capacitance characteristics of collector junctions of planar bipolar epitaxial transistors. It uses an exponential model to represent the impurity distribution and makes available by non-destructive techniques base impurity profile constant, background concentration and collector junction depth from terminal measurements. The methods take care of such aspects of device geometry which are particular to small area high frequency transistors. Procedures are proposed for systematic evaluation of stray and sidewall capacitances. The latter can be used to monitor junction depth. Of interest for quick estimation of parameters is a method that utilises derivatives of the C(V) plot and does not require evaluation of strays.  相似文献   
35.
This paper presents an improved low voltage cascode and flipped voltage follower (FVF) based current mirror with the enhancement of the bandwidth obtained by using a compensation resistor between the gates of the primary transistor pair. In this technique a carefully determined resistance is used in the diode connected MOS transistor of the current mirror for enhancing the bandwidth. Active realization of the compensation resistance using MOS operating in the triode region has also been applied to both the cascode and FVF based current mirror circuits. The proposed circuits have been simulated using PSpice for 0.25 μm CMOS technology and the obtained results are compared with their uncompensated topologies to show their effectiveness.  相似文献   
36.
In this article, morphological modification of Saccharum spontaneum L, a natural fiber through graft copolymerization with methylmethacrylate using ferrous ammonium sulfate—potassium per sulfate redox initiator has been reported. Different reaction parameters such as reaction temperature, time, initiator molar ratio, monomer concentration, pH and solvent were optimized to get maximum graft yield (144%). The graft copolymers thus formed were characterized by Fourier transform infrared, scanning electron microscopy, X‐ray diffraction and thermogravimetric, differential thermal analysis, and differential thermogravimetric techniques. Graft copolymer has been found to be more moisture resistant and also showed higher chemical and thermal resistance. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
37.
In the present study, the synthesis of novel semi‐interpenetrating network (Semi‐IPN) hydrogel based on gum rosin alcohol‐psyllium (GrA‐Psy) has been reported. (Gum rosin alcohol‐psyllium)‐crosslinked‐poly(acrylic acid) [termed as (GrA‐Psy)‐cl‐poly (AA)] was synthesized using potassium persulphate (KPS) as an initiator and N, N? methylene‐bis‐acrylamide (MBA) as crosslinker by free radical graft co‐polymerization technique. The prepared semi‐IPN was characterized using FTIR, XRD, and FE‐SEM. Further, the synthesized hydrogel was evaluated for the removal of malachite green (MG) dye from aqueous solution. Dye adsorption data was analyzed through various isotherm and kinetic models. Thermodynamic parameters and reusability of the synthesized adsorbent were also assessed. POLYM. ENG. SCI., 59:1416–1427 2019. © 2019 Society of Plastics Engineers  相似文献   
38.
Kaur  Navneet  Jindal  Neeru  Singh  Kulbir 《Multimedia Tools and Applications》2020,79(43-44):32037-32063
Multimedia Tools and Applications - With the technology progress, a plethora of freely accessible software has questioned the authenticity of digital images. This field is continuously creating...  相似文献   
39.

With the extensive use of multimedia on internet and easy approachability of powerful image and video editing software, doctored visual contents have been extensively appearing in our electronic-mail in-boxes, Whatsapp, Facebook or any other social media. Recently, attempting blind tampering in visual contents have been progressively adopted. This paper presents a collaborative survey on detection of such attempts. Our aim is to establish an effective path, for researchers working in the field of image and video forensics, to unfold new aspects of forgery. This paper will avail the comprehensive study that will assist the researchers to go through the various challenges encountered in the previous work. The focus of this paper is to review the splicing and copy–move forgery detection methods in images as well as inter and intra-frame forgery challenges in videos, highlighting the commonly used datasets and hence assisting new researchers to work on with. The efficacy of the paper is that such collaborative survey under one umbrella is not available yet.

  相似文献   
40.
Multimedia Tools and Applications - Breast tumour is one of the leading causes of death among women worldwide. Researchers are working hard to develop early and improved detection tools for breast...  相似文献   
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