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21.
Active targeting using biological ligands has emerged as a novel strategy for the targeted delivery of diagnostic agents to tumor cells. Conjugating functional targeting moieties with diagnostic probes can increase their accumulation in tumor cells and tissues, enhancing signal detection and, thus, the sensitivity of diagnosis. Due to their small size, ease of chemical synthesis and site-specific modification, high tissue penetration, low immunogenicity, rapid blood clearance, low cost, and biosafety, peptides offer several advantages over antibodies and proteins in diagnostic applications. Epidermal growth factor receptor (EGFR) is one of the most promising cancer biomarkers for actively targeting diagnostic and therapeutic agents to tumor cells due to its active involvement and overexpression in various cancers. Several peptides for EGFR-targeting have been identified in the last decades, which have been obtained by multiple means including derivation from natural proteins, phage display screening, positional scanning synthetic combinatorial library, and in silico screening. Many studies have used these peptides as a targeting moiety for diagnosing different cancers in vitro, in vivo, and in clinical trials. This review summarizes the progress of EGFR-targeting peptide-based assays in the molecular diagnosis of cancer.  相似文献   
22.
The effect of air temperature (AT) and slice thickness (ST) on the quality and drying kinetics of tomato slices were studied. The drying period of tomato slices to reach the moisture content of 15% (wb) ranged from 2.6 to 18.7 h. The water diffusivity, activation energy, and resistance to diffusion ranged from 1.4 × 10?10 to 2.8 × 10?9 m2/s, 21.25 to 23.4 kJ/mol, and from 939 to 4590 m2 s/kg, respectively. Drying had a significant effect on ascorbic acid, soluble solid, acidity, and pH (P = 0.01). The ascorbic acid degradation was greatly influenced by ST. The results show that time-temperature superposition technique (TTST) was very efficient in the modeling of the drying process. The proposed TTST provides a novel alternative in curve-fitting exercise of drying data. Neural networks also showed favorable performance in estimating the drying functions.  相似文献   
23.
The bulk NiFe2?xBixO4 ferrites with various Bi3+ concentration (x=0, 0.1, 0.15) were synthesized via sol–gel procedure, starting from nickel, bismuth and iron nitrate powders, followed by the conventional thermal treatment. The structural and magnetic properties of the as-prepared ferrites were studied by means of X-ray diffraction, alternating gradient force magnetometry and Faraday balance. The anisotropy constant was determined by the law of approach to saturation (LAS) model. An increasing Bi3+ concentration in NiFe2?xBixO4 leads to a decrease in the saturation magnetization, Néel temperature and the anisotropy constant of the material.  相似文献   
24.
ZrP2O7 nanoparticle catalyzed one-pot synthesis of 4H-pyran scaffolds installing a one-pot three-component coupling reaction of an aldehyde, malononitrile, and ethyl acetoacetate. Also the synthesis of 1,4-dihydropyridines was investigated by using aldehydes, ethyl acetoacetate and ammonium acetate as utilizing nano structured ZrP2O7 as an efficient catalyst in ethanol. The attractive features of this process are mild reaction conditions, reusability of the catalyst, short reaction times, easy isolation of the products, and excellent yields.  相似文献   
25.
The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd+ Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution of PdNi nanoparticles, and lower dissociation and desorption barriers. Comparison of the catalysts synthesized by MIL-101(Cr) and MIL-101-NH2(Cr) as the supports of metals showed that Pd/MIL-101-NH2(Cr) outperforms Pd/MIL-101-(Cr) because of the higher electron density of Pd resulting from the electron donor ability of the NH2 functional group. However, the same activities were observed for Pd70Ni30/MIL-101(Cr) and Pd70Ni30/MIL-101-NH2(Cr), which is due to a less uniform distribution of Pd nanoparticles in Pd70Ni30/MIL-101-NH2(Cr) originated from amorphization of MIL-101-NH2(Cr) structure during the reduction process. In contrast, Pd70Ni30/MIL-101(Cr) revealed the stable structure and activity during reduction and CO oxidation for a long time.  相似文献   
26.
The proposed research describes the synthesis and characterization of platinum nanoparticles loaded on activated carbon (Pt-NP-AC) and its efficient application as novel adsorbent for efficient removal of reactive orange 12 (RO-12). The influences of effective parameters following the optimization of variables on removal percentages, their value was set as 0.015 g Pt-NP-AC, pH 1, contact time of 13 min. At optimum values of all variables at 25 and 50 mgL−1 of RO-12 enthalpy (ΔH0) and entropy (ΔS0) changes was found to be 59.89 and 225.076, respectively, which negative value of ΔG0 shows a spontaneous nature, and the positive values of ΔH0 and ΔS0 indicate the endothermic nature and adsorption organized of dye molecule on the adsorbent surface. Experimental data was fitted to different kinetic models including first-order, pseudo-second-order, Elovich and intra-particle diffusion models, and it was seen that the adsorption process follows pseudo-second-order model in consideration to intra-particle diffusion mechanism. At optimum values of all variables, the adsorption process follows the second-order kinetic and Langmuir isotherm model with adsorption capacity 285.143 mg g−1 at room temperature.  相似文献   
27.
The present work deals with application of 25-2 fractional factorial design (FFD) to evaluate the operating parameters on starch separation from synthetic starchy wastewater using a hydrophilic polyethersulfone membrane with 0.65 μm pore size in a plate and frame handmade membrane module. The analysis of variance (ANOVA) combined with F-test was also used to recognize non-significant terms. The performance of the filtration process was evaluated by calculating the COD removal percentage (rejection factor) and permeate flux. In this experiment, five input parameters were surveyed, including trans membrane pressure (TMP), flow and temperature of feed, pH and concentration of wastewater. In this experiment, real wastewater was not used but synthetic starchy wastewater was prepared using starch. Two models were obtained from experimental data, capable of predicting COD removal percentage and permeate flux in different conditions. The predicted values obtained from the regression models were close to the actual ones. For the reduction of fouling, cleaning in place (CIP) method was used.  相似文献   
28.
29.
The simultaneous influence of NaCl, KCl and KI salts and well known sodium dodecyl sulfate (SDS) surfactant on the interfacial tension (IFT) of conventionally used chemical system of toluene-water was studied. The concentration range of salts was within (0.010 to 0.075) mol/dm3 and of surfactant within (1.7 to 26.0)×10?5 mol/dm3. SDS adsorption on interface is highly intensified in the presence of salts and IFT can reach to 67.1% of its initial value. Accordingly, the role of ions was investigated and the order of salts effectiveness was revealed as KI?KCl>NaCl. The obtained data, with both effects, were nicely reproduced using an equation of state, based on Gibbs adsorption equation and the Langmuir isotherm. Two relevant important adsorption parameters exhibited reasonable variations. Furthermore, the general revealed linear variation of IFT with a previously defined “effective concentration” indicates the strong influence of the surfactant counterions.  相似文献   
30.
Novel results were obtained by selection of chitosan treatment parameters on cotton fabrics to obtain antimicrobial properties against E. coli, gram-negative bacteria. Taguchi experimental design was used in this study and microbial reduction rate was considered as the response. The signal-to-noise and the analysis of variance (ANOVA) were used to find the optimum levels to indicate the impact of treatment parameters on antimicrobial properties. The antimicrobial behavior of the fabric against bacterium as a function of each parameter was plotted. A verification test was also performed to prove the validity of Taguchi technique for this study after the determination of parameters’ optimum levels. Also the effect of chitosan and the mordanting on the dyeing properties of cotton fabrics with natural dyes such as walnut hull and safflower was investigated by measuring the color strength (K/S values) of the treated and untreated substrates at various concentrations. The results revealed that the K/S of dyed chitosan-treated cottons increased compared to untreated samples. In addition, antimicrobial properties of natural-dyed treated and untreated fabrics were determined. Walnut hull and safflower have shown antimicrobial properties. Although dyeing the chitosan-treated fabric reduced its antimicrobial effects but the results showed that chitosan-treated cotton fabrics had excellent antimicrobial properties against E. coli. Applying Taguchi experimental design for treating cotton fabrics with chitosan and utilizing these native natural dyes have never been used elsewhere.  相似文献   
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