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31.
The Co1?x Zn x (x=0.4?0.5) nanorods were synthesized via an AC electrochemical deposition method into anodized aluminum oxide (AAO) templates at different voltages ranging from 10 to 18 V, and nanorods of varying concentrations of Co and Zn were obtained. The characterization tools were used to examine different aspects of nanorods, e.g., shape, size, morphology, chemical composition, and magnetic behavior. Scanning electron microscope (SEM) images show that CoZn nanorods have length L=1μm and diameter d=50 nm. The grain size was calculated to be 25.4 nm using an X-ray diffraction (XRD) technique. The XRD also shows some other phases of ZnCoO. The M?H loops measured by a vibrating sample magnetometer (VSM) at room temperature show pure ferromagnetic behavior at all AC potentials. The nanorods show magnetic isotropic behavior due to strong magnetic interactions and presence of random nanorods. The potential-dependent coercivity H c and saturation magnetization M s show a non-linear curve which is explained on the basis of magnetic islands and domain wall pinning. This study is useful to tune the magnetic properties of nanorods by a simple and low-cost technique.  相似文献   
32.

Secure data transmission over the public channels have high impact and increasingly important due to theft and manipulation in contents. The requirement of public/ private organizations to develop an efficient scheme to provide security to their contents. We developed a digital contents encryption scheme based Arnold scrambling and Lucas series, which is very simple to implement but almost impossible to breach in this article. We perform encryption at standard images by using Lucas series at different iterations of scrambled images of Arnold transform. Numerical simulation analyses performed to analyze the efficiency and effectiveness of the projected structure.

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33.
The objective of this research is to construct a type-II heterojunction interface for effective photoelectrochemical (PEC) water splitting for hydrogen generation. A series of ZnSe/g-C3N4 heterojunctions is prepared by ultrasonication procedure and tested for PEC water splitting for the first time. The successful formation of ZnSe/g-C3N4 is confirmed by phase, morphological and optical analysis. Linear sweep voltammetry of 0.05 ZG (0.05% ZnSe/g-C3N4) showed a six-fold higher photocurrent density of 500 μA than g-C3N4. These results are supported by the Tafel slopes and PL (photoluminescence spectroscopy) studies by showing the smallest slope and lesser electron-hole recombination for 0.05 ZG. Increased lifetime of 107 ms and a higher donor density of 3.6 × 1019 cm?3 for 0.05 ZG is observed. The smallest semicircle for 0.05 ZG in EIS implies the least charge transfer resistance among the prepared heterojunctions. All the results comply with each other showing the successful formation of type-II heterojunction for enhanced PEC water splitting.  相似文献   
34.
Graphene oxide (GO) was synthesized by Hummers method. GO and tungsten oxide (WO3) composites were successfully prepared by deposition of WO3 on GO surface to make efficient visible light catalyst. Scanning electron microscopy of pure GO revealed that GO films are folded with kinked and wrinkled edges. The interspaces layers are partially filled by WO3 nanoparticles with their less wrinkled edges and smooth surface of composite. Moreover, composite sheets are thin and transparent which allow easy penetration of light. EDS showed the presence of C, O, and W in GO/WO3 composites with no impurity. UV-Vis diffused reflectance spectra showed red shift with the increase in WO3 contents. Raman spectra of GO and GO/WO3 composite show G and D bands. These bands reduced in intensity in composite sample due to removal of oxygenated functional groups with some new peaks of WO3. FT-IR confirmed successful oxidation of graphite into GO with reduction in GO because oxide-related bond groups decrease after reduction. The transmittance peaks of WO3 in composite sample are appeared indicating W-O-C linkages. The highest visible light activity of the composite is due to easy penetration of light with deposition of WO3, low band gap, and new linkages.  相似文献   
35.
The quality assurance and authentication of crude herbal drugs play important role in the effective therapeutic effect of herbal drug and their products. There are many reported problems in quality assurance of herbal crude drugs concerning to their correct identification. The present study was designed with the aim to document the authentication and quality assurance of the herbal crude drugs (Argyrolobium roseum and Viola stocksii) thorough light microscopy (LM) and scanning electron microscopy (SEM). The detailed foliar anatomical studies showed polygonal epidermal cells having anticlinal walls in Argyrolobium roseum while rounded epidermal cells were observed in Viola stocksii. The anomocytic stomata type was observed in Argrolobium roseum while actinocytic was noticed in Viola stocksii. The pollen of studied species appeared as tricolporate showing reticulate exine sculpturing in Argrolobium roseum while fine perforations were recorded in Viola stocksii. Furthermore, quantitative analysis of phenols, flavonoids, and antioxidant activity showed high flavonoid and phenol content in Argyrolobium roseum as compared with Viola stocksii. It was observed that Argyrolobium roseum was discriminated from the Viola stocksii based on the leaf and pollen micromorphological traits by using LM and SEM techniques. It was concluded that LM and SEM techniques were found useful for the quality assurance of botanicals and their authentication.  相似文献   
36.
The medicinal plants are utilized globally considering the cheap and chemical free source, but their correct identification and authentication is prerequisite for safety and efficacy of plant‐based medicines. The present study encompassed traded medicinal plants (16) with high therapeutic value from diverse families like Brassicaceae, Berberidaceae, Malvaceae, Salicaceae, Myrtaceae, Papilionaceae, Ascelpiadaceae, Colchicaceae, Violaceae, and Vitaceae for detailed microscopic study of characters that is, morphology, pollen shape and sizes, P/E ratio, pore length and width, spine length, colpi dimensions, and exine sculpture pattern. The plants showed noteworthy differences in microscopy of Wattakaka volubilis having pollinia, translator and corpusculum like structures while pores were visible in Colchicum luteum, Alcea rosea, and Hibiscus syriacus. The spines were observed in Centipeda minima, A. rosea, and H. syriacus being dimorphic spines in A. rosea and monomorphic in H. syriacus. The exine sculpturing pattern was reticulate in mostly studied plants however distinctive exine pattern was noted in Berberis aristata and Berberis lyceum. The highest polar diameter, equatorial diameter and exine thickness among studied plants were observed in H. syriacus (161 μm), C. luteum (50 μm) and Vitis jacquemontii (1.10), respectively. Thus, microscopy of medicinal plants in addition to other taxonomic evidence offers a supportive skill in authentication, consequently utilization by local consumers and pharmaceutical industries.  相似文献   
37.
BACKGROUND: Patients with chronic idiopathic constipation can be difficult to manage either medically or surgically. We report our experience of long-term follow-up of 21 patients who had undergone colectomy with ileorectal anastomosis for difficult chronic idiopathic constipation. METHODS: The patients (19 female, 2 male) were aged 26-68 (median = 46) years and had undergone subtotal colectomy 5-12 (median = 8) years before their assessment. They answered a questionnaire about severity of abdominal pain, bloating, urgency, and straining. They also completed the hospital anxiety and depression questionnaire. Fifteen ulcerative colitis patients with panproctocolectomy and 13 colon cancer patients with colonic resection who had a similar follow-up period served as control groups. The following assessments were performed in chronic idiopathic constipation patients with subtotal colectomy: a) oesophageal manometry; b) scintigraphic gastric emptying test; c) review of barium follow-through; d) glucose H2 breath test; e) urodynamic studies; and f) autonomic function tests. RESULTS: Twenty-four per cent of patients with chronic idiopathic constipation had a family history of difficult constipation requiring hospital investigations and treatment. At the time of assessment abdominal pain, bloating, urgency, and straining at defecation were all significantly more frequent in patients with chronic idiopathic constipation with colectomy than in the control groups with colectomy. Seventy-one per cent of chronic idiopathic constipation patients had at least one episode of intestinal obstruction after subtotal colectomy, which is significantly higher (P < 0.01) than in the control groups (ulcerative colitis, 13%; colonic carcinoma, 8%). In patients with chronic idiopathic constipation, among those studied, 68% had some oesophageal motor dysfunction: 19% delayed gastric emptying; 10%, prolonged small-bowel transit on barium follow-through; 54%, abnormal urodynamic variables; and 14%, abnormal autonomic function tests. CONCLUSIONS: This study shows considerable morbidity in a selected cohort of patients with chronic idiopathic constipation who were sufficiently disabled by their symptoms to undergo subtotal colectomy. They had more abdominal and rectal symptoms and more frequent intestinal obstructive episodes than control groups with colonic resection. Evidence of generalized smooth-muscle dysfunction and familial occurrence of constipation suggests a primary chronic intestinal pseudo-obstruction-like disorder in some of these patients.  相似文献   
38.

Emotion recognition from facial images is considered as a challenging task due to the varying nature of facial expressions. The prior studies on emotion classification from facial images using deep learning models have focused on emotion recognition from facial images but face the issue of performance degradation due to poor selection of layers in the convolutional neural network model.To address this issue, we propose an efficient deep learning technique using a convolutional neural network model for classifying emotions from facial images and detecting age and gender from the facial expressions efficiently. Experimental results show that the proposed model outperformed baseline works by achieving an accuracy of 95.65% for emotion recognition, 98.5% for age recognition, and 99.14% for gender recognition.

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39.

Impacts of gold nanoparticles on MHD Poiseuille flow of nanofluid in a porous medium are studied. Mixed convection is induced due to external pressure gradient and buoyancy force. Additional effects of thermal radiation, chemical reaction and thermal diffusion are also considered. Gold nanoparticles of cylindrical shape are considered in kerosene oil taken as conventional base fluid. However, for comparison, four other types of nanoparticles (silver, copper, alumina and magnetite) are also considered. The problem is modeled in terms of partial differential equations with suitable boundary conditions and then computed by perturbation technique. Exact expressions for velocity and temperature are obtained. Graphical results are mapped in order to tackle the physics of the embedded parameters. This study mainly focuses on gold nanoparticles; however, for the sake of comparison, four other types of nanoparticles namely silver, copper, alumina and magnetite are analyzed for the heat transfer rate. The obtained results show that metals have higher rate of heat transfer than metal oxides. Gold nanoparticles have the highest rate of heat transfer followed by alumina and magnetite. Porosity and magnetic field have opposite effects on velocity.

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40.
You  Lihua  Yang  Xiaosong  Pan  Junjun  Lee  Tong-Yee  Bian  Shaojun  Qian  Kun  Habib  Zulfiqar  Sargano  Allah Bux  Kazmi  Ismail  Zhang  Jian J. 《Multimedia Tools and Applications》2020,79(31-32):23161-23187

Virtual characters are 3D geometric models of characters. They have a lot of applications in multimedia. In this paper, we propose a new physics-based deformation method and efficient character modelling framework for creation of detailed 3D virtual character models. Our proposed physics-based deformation method uses PDE surfaces. Here PDE is the abbreviation of Partial Differential Equation, and PDE surfaces are defined as sculpting force-driven shape representations of interpolation surfaces. Interpolation surfaces are obtained by interpolating key cross-section profile curves and the sculpting force-driven shape representation uses an analytical solution to a vector-valued partial differential equation involving sculpting forces to quickly obtain deformed shapes. Our proposed character modelling framework consists of global modeling and local modeling. The global modeling is also called model building, which is a process of creating a whole character model quickly with sketch-guided and template-based modeling techniques. The local modeling produces local details efficiently to improve the realism of the created character model with four shape manipulation techniques. The sketch-guided global modeling generates a character model from three different levels of sketched profile curves called primary, secondary and key cross-section curves in three orthographic views. The template-based global modeling obtains a new character model by deforming a template model to match the three different levels of profile curves. Four shape manipulation techniques for local modeling are investigated and integrated into the new modelling framework. They include: partial differential equation-based shape manipulation, generalized elliptic curve-driven shape manipulation, sketch assisted shape manipulation, and template-based shape manipulation. These new local modeling techniques have both global and local shape control functions and are efficient in local shape manipulation. The final character models are represented with a collection of surfaces, which are modeled with two types of geometric entities: generalized elliptic curves (GECs) and partial differential equation-based surfaces. Our experiments indicate that the proposed modeling approach can build detailed and realistic character models easily and quickly.

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