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The coverage, thickness, and crystallinity of ZnIn2S4 (ZIS) shells on SiO2 core nanoparticles (SiO2@ZIS) were systematically investigated using microwave-assisted solvothermal methods aided by the addition of acid in ethanolic medium. The surface modification of the SiO2 cores with (3-mercaptopropyl)trimethoxysilane was found to be critical to generate a homogeneous coverage of ZnIn2S4. The SiO2@ZIS core-shell nanoparticles exhibited the best coverage but poor crystallinity when synthesized in pure ethanol, whereas best crystallinity but poor coverage was observed when synthesized in an aqueous solution. The addition of selected amounts of acid (HCl) led to improved crystallinity in the ethanolic medium. The thickness of the ZIS shell could be controlled in an ethanolic solution by judiciously varying the amounts of acid and the concentration of the ZIS precursor. Increasing the concentration of the ZIS precursor to twice the standard concentration in ethanolic solution with the addition of 100 μL of HCl afforded better crystallinity, homogeneous coverage, and optimal photocatalytic hydrogen production.

The coverage, thickness, and crystallinity of ZnIn

Background Application of chromosomal microarray analysis (CMA) to investigate the genetic characteristics of fetal growth restriction (FGR) without ultrasonic structural anomalies at 18–32 weeks. Methods This study includes singleton fetuses with the estimated fetal weight (EFW) using the formula of Hadlock C below the 10th percentile for gestational age. FGRs without structural anomalies were selected, and the ones at high risk of noninvasive prenatal testing for trisomy 13, 18 and 21 would be excluded. The cases were divided into two groups: early-onset group (

Titanium dioxide (TiO 2 ) has gained increasing interest in materials research due to its outstanding properties and promising applications in a wide range of fields. From this perspective, we report the synthesis of custom-designed anatase TiO 2 submicrometer particles coated with partial Au shells (ATiO 2 -AuShl). The synthetic strategy used herein yields uniformly shaped monodisperse particles. Amorphous TiO 2 core particles were synthesized using template-free oxidation and hydrolysis of titanium nitride (TiN); subsequent hydrothermal treatment generated anatase TiO 2 (ATiO 2 ) particles. Coating ATiO 2 particles with partial Au shells was accomplished using a simple seeded-growth method. Evaluation of the optical properties of these ATiO 2 -AuShl particles showed that these submicrometer composites exhibited an intense absorption peak for TiO 2 in the UV region (∼326 nm) and a broad extinction band in the visible range (∼650 nm) arising from the incomplete Au shell. These ATiO 2 -AuShl composite particles provide a unique and effective means for broadening the optical response of TiO 2 -based nano- and micron-scale materials. The simplicity of our synthetic method should broaden the application of ATiO 2 -AuShl particles in various visible light-driven technologies.

Gold-silver nanoshells (GS-NSs) having a tunable surface plasmon resonance (SPR) were employed to facilitate charge separation of photoexcited carriers in the photocalytic production of hydrogen from water. Zinc indium sulfide (ZnIn2S4; ZIS), a visible-light-active photocatalyst, where the band gap varies with the [Zn]/[In] ratio, was used as a model ZIS system (E(g) = 2.25 eV) to investigate the mechanisms of plasmonic enhancement associated with the nanoshells. Three types of GS-NS cores with intense absorptions centered roughly at 500, 700, and 900 nm were used as seeds for preparing GS-NS@ZIS core-shell structures via a microwave-assisted hydrothermal reaction, yielding core-shell particles with composite diameters of ∼200 nm. Notably, an interlayer of dielectric silica (SiO2) between the GS-NSs and the ZIS photocatalyst provided another parameter to enhance the production of hydrogen and to distinguish the charge-transfer mechanisms. In particular, the direct transfer of hot electrons from the GS-NSs to the ZIS photocatalyst was blocked by this layer. Of the 10 particle samples examined in this study, the greatest hydrogen gas evolution rate was observed for GS-NSs having a SiO2 interlayer thickness of ∼17 nm and an SPR absorption centered at ∼700 nm, yielding a rate 2.6 times higher than that of the ZIS without GS-NSs. The apparent quantum efficiencies for these core-shell particles were recorded and compared to the absorption spectra. Analyses of the charge-transfer mechanisms were evaluated and are discussed based on the experimental findings.

Based on the threats of cloud computing security, combined with the principle of private cloud computing, this paper introduces the variable dimension fractal theory into the cloud computing and security policy model, and puts forwards multidimensional data model C2MDSM of the cloud computation. The model can protect 2D and 3D protection of user information in a private cloud space. Through the 3D fractal it greatly improves the user use of cloud resources, and improves the security of information, which realizes the true sense of the reasonable distribution for cloud resources. In order to verify the validity of the mathematical model and the algorithm designed in this paper, we use the MATLAB software to draw 2D and 3D fractal, and obtain the number of cloud users, security level and calculation residual results. It provides the technical reference for the research on cloud computing.

Cloud computing can dynamically allocate the software or hardware resource and information resource in accordance with the needs of different computer users, so as to expand the virtual resources of computer, but data information exists a big security risk in the process of data parallel calculation or the data sharing, so it needs to carry out the risk assessment on the security of signal. In cloud computing, this paper introduces the second-order difference quotient calculation principle in the model of information risk assessment that has accelerated the speed of information risk assessment, and adopts second order linear security authentication model that has strengthened the security of the cloud computing. In order to verify the validity and reliability of the model, this paper uses C program language to design the algorithm and inspects the cloud data with possible existing risk, and then it obtains the deviation curve of numerical calculation and theoretical value, which provides the technical reference for the research of cloud information security technology.

Investment in fixed assets is the main aspects of the national government to implement macro-control economy, and it is also the pillar of national economic growth. At the same time, the investment of enterprise fixed assets is to upgrade its commercial value and add the main source of income. However, in the current business competition, many enterprises especially private enterprises often make the mistake of judgment, resulting in too much investment, investment deviation and other consequences, which blocks the development of enterprises and the growth of the national economy. Firstly, this paper analyzes the computer aided technology, and constructs the fixed asset investment model based on database management technology, and does computer simulation on this model. The results show that the investment model can help enterprises to make reasonable investment decision and support theory, which promotes the enterprise value.

To investigate the effect of solanine on the growth of human prostate cancer cell xenograft in nude mice.Human prostate cancer Du145 cells were injected into the subcutaneous layers on the back of nude mice. After a week, the mice bearing subcutaneous tumor graft were randomly divided into solanine treatment group and saline control group for treatment for 3 weeks. The tumor grafts were then harvested to evaluate the inhibition rate. The mRNA and protein expressions of cell cycle-related genes in the tumors were detected by qRT-PCR and Western blotting, respectively, and tumor cell apoptosis was detected using TUNEL method.The tumor growth rate in solanine-treated group was significantly slower than that in the control group (P0.01). The mRNA and protein expressions of C-myc, cyclin D1, cyclin E1, CDK2, CDK4 and CDK6 were significantly inhibited by solanine. Solanine significantly up-regulated p21 mRNA and protein expression in the tumors and induced a higher apoptosis rate of the tumor cells than saline (P0.01).The tumor-inhibition effect of solanine is probably mediated by regulating the expressions of genes related with G1/S cell cycle arrest and cell apoptosis.

To assess the value of fluorescence in situ hybridization (FISH) in the diagnosis of common chromosome number aberration in spontaneously aborted fetuses.A total of 100 spontaneously aborted fetuses were analyzed by G-banding and by FISH to test chromosome number aberration mainly for chromosomes 13, 18, 21, X and Y, and the results of FISH test was assessed according to those by G-banding test.FISH results were well consistent with those by G-banding test. FISH test identified trisomy in 32 samples and polyploidy in 7 samples. Two samples with cell culture failure were found to have trisomy 16 by FISH. Discrepancies in the results between the two tests occurred in 3 samples, but the results of FISH were verified by other methods. Kappa test between FISH technology and G-banding showed a good consistency between FISH and karyotyping (P0.05).FISH is an effective and rapid method for detecting chromosome number aberration in spontaneously aborted fetuses, and the combination of FISH and karyotyping provides more reliable diagnostic evidence.

To investigate the value of fetal chromosomal karyotype analysis in cases of early spontaneous abortion.Chorionic villus specimens obtained from 110 cases of early spontaneous abortion were cultured for karyotype analysis.Of the 110 cases, chorionic villus was successfully cultured in 103 cases (93.7%), and abnormal embryo karyotypes were identified in 52 cases (50.5%). Trisomy was the most frequent embryo karyotype abnormalities in these cases, and chromosomal aberration occurred in 29 cases (52.9%) of the first spontaneous abortion and in 23 cases (42.6%) of repeated abortions. Female fetuses accounted for 75.5% (78 cases) in the spontaneously aborted fetuses and for 67.3% (35 cases) in fetuses with chromosomal abnormalities.Embryo chromosomal abnormality is the most important reason of early spontaneous abortion, and karyotype analysis of the villus helps identify the causes of abortion and ensure the success of the next pregnancy.