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Background: Glioma, the most common tumour in children next to leukaemia, is difficult to treat, with a poor prognosis and high recurrence rate. Xeroderma pigmentosum group G (XPG) plays a key role...

To investigate the regulation of long non-coding RNA plasmacytoma variant translocation 1 (LncRNA PVT1) on proliferation, invasion, and aerobic glycolysis in glioma cells via miR-140-5p.Sixty patients with glioma treated in our hospital were recruited. The expression of PVT1 in tissues and cells was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), and the effects on the prognosis were observed. Glioma cell lines U87 and T98MG were either stably or transiently transfected with over-expression or inhibition vectors. Cell counting kit-8 (CCK-8), transwell, glucose, and lactate detection were employed to measure cell proliferation, invasion, and aerobic glycolysis after transfection. The correlation between PVT1 and miR-140-5p was determined by Dual-Luciferase reporter assay. RNA pull-down and RNA immunoprecipitation (RIP) test were adopted to indicate the correlation between PVT1 and miR-140-5p.PVT1 was highly expressed and had superior diagnostic value in gliomas, and the high expression of PVT1 resulted in poor prognosis of patients. Over-expressing PVT1 increased cell proliferation, invasion, and aerobic glycolysis, while inhibiting PVT1 yielded opposite outcome. Dual-Luciferase reporter assay confirmed that PVT1 could target miR-140-5p. Functional analysis showed that over-expression of miR-140-5p inhibited proliferation, invasion, and aerobic glycolysis in glioma cells. Rescue experiment found that the inhibitory effect of miR-140-5p could be eliminated by up-regulating PVT1 expression.PVT1 promotes proliferation, invasion, and aerobic glycolysis in glioma cells by regulating miR-140-5p.

Non-alcoholic fatty liver disease and obesity have interconnected genes, but it can also occur in non-obese population with body mass index25 kg/m(2). Non-obese type of non-alcoholic fatty liver disease mostly occurs in Asia. There is no significant difference between obese and non-obese type of non-alcoholic fatty liver in histological examination of liver biopsies. Visceral obesity, high fructose and cholesterol intake, and genetic factors such as APOC3 gene mutation are closely related to non-obese type of non-alcoholic fatty liver. Generally speaking, non-alcoholic steatohepatitis has an increased mortality rate, mainly due to cardiovascular causes, and has no link with other metabolic factors. Although data on the impact of mortality from non-obese type of non-alcoholic fatty liver disease are incomplete and limited, however diagnosis, management, and treatment may be important. Lifestyle changes to reduce visceral obesity, including dietary changes and physical activity, remain the main treatment options for patients with non-obese type of non-alcoholic fatty liver disease.非酒精性脂肪性肝病和肥胖有相关的基因，但是也可发生在人体质量指数25 kg/m(2)的非肥胖人群中。这种非肥胖型非酒精性脂肪性肝病多发生在亚洲。在肝穿刺活组织病理学检查中肥胖型和非肥胖型非酒精性脂肪性肝病没有明显的差异。内脏肥胖、高果糖和胆固醇摄入、以及遗传因素如APOC3基因变异等与非肥胖型非酒精性脂肪性肝病密切相关。一般来说，非酒精性脂肪性肝炎病死率增加，主要是心血管病因，与其他代谢因素无关。虽然关于非肥胖型非酒精性脂肪性肝病病死率影响的数据并不完整且有限，但诊断、管理、治疗可能很重要。改变生活方式以减少内脏肥胖，包括饮食变化和体力活动，仍然是非肥胖型非酒精性脂肪性肝病患者主要治疗方案。.

Artificial neural networks (NNs) are trained, based on the numerical database, to predict the no-wall and ideal-wall β N limits, due to onset of the n = 1 (n is the toroidal mode number) ideal external kink instability, for the HL-2M tokamak. The database is constructed by toroidal computations utilizing both the equilibrium code CHEASE (Lütjens et al 1992 Comput. Phys. Commun. 69 287) and the stability code MARS-F (Liu et al 2000 Phys. Plasmas 7 3681). The stability results show that (1) the plasma elongation generally enhances both β N limits, for either positive or negative triangularity plasmas; (2) the effect is more pronounced for positive triangularity plasmas; (3) the computed no-wall β N limit linearly scales with the plasma internal inductance, with the proportionality coefficient ranging between 1 and 5 for HL-2M; (4) the no-wall limit substantially decreases with increasing pressure peaking factor. Furthermore, both the NN model and the convolutional neural network (CNN) model are trained and tested, producing consistent results. The trained NNs predict both the no-wall and ideal-wall limits with as high as 95% accuracy, compared to those directly computed by the stability code. Additional test cases, produced by the Tokamak Simulation Code (Jardin et al 1993 Nucl. Fusion 33 371), also show reasonable performance of the trained NNs, with the relative error being within 10%. The constructed database provides effective references for the future HL-2M operations. The trained NNs can be used as a real-time monitor for disruption prevention in the HL-2M experiments, or serve as part of the integrated modeling tools for ideal kink stability analysis.

Accumulating evidence has suggested that aberrant expression of microRNAs (miRNAs) is associated with non-small cell lung cancer (NSCLC) proliferation, migration, invasion and chemotherapy resistance. Cullin4A (CUL4A) has been previously reported to desensitize NSCLC cells to chemotherapy treatment. However, whether miRNAs regulate CUL4A to promote chemotherapy resistance remains unknown.Tissues were obtained from 40 NSCLC patients who received surgery at the Yancheng City No. 1 People's Hospital. Cell Counting Kit-8 (CCK-8) assays were applied for the detection of cell proliferation; mRNA and protein levels were determined by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) and Western blot, respectively. The interaction between mRNA 3'UTR and miRNA was predicted by TargetScan and verified by Dual-Luciferase reporter assay.In the present study, miR-363-3p levels were revealed to be significantly decreased in tumor tissues obtained from NSCLC patients compared with adjacent normal tissues. The results of the CCK-8 assays showed that the overexpression of miR-363-3p may slightly inhibit the proliferation of A549 and H23 cells. Notably, the transfection with miR-363-3p antagonists reduced the sensitivity of A549 and H23 cells to gemcitabine treatment, whereas the overexpression of miR-363-3p markedly increased the sensitivity of A549 and H23 cells to gemcitabine treatment. Furthermore, CUL4A mRNA and protein levels were revealed to be decreased in A549 cells transfected with miR-363-3p mimics. The Dual-Luciferase reporter assay results further suggested that CUL4A represents a target gene of miR-363-3p.The results indicated that decreased miR-363-3p expression enhanced gemcitabine resistance in NSCLC cells via regulation of CUL4A.

It is hard to accurately meter the fuel feed into the furnace for a double-in and double-out pulverizing system, which affects the fuel control quality and also the main steam pressure of a boiler. A correction method for the indirect measurement model of the coal metering feed into the furnace for double-in and double-out pulverizing system is proposed based on the combustion state diagnosis of a burner using fuzzy C-mean clustering method, of which is applied in a 620MW super critical power unit. The engineering application results suggested that the method of this work is effective to improve the fuel control quality during the mill start and stop process. By using the method of this work, the controlling deviation between the target value and the measured value of the main steam pressure is within 0.2 MPa, while it is about 0.6 MPa when the fuel control is without correction.

A new damping model on the resistive wall mode (RWM) instability is studied, via the turbulence induced plasma viscosity (in short, turbulent viscosity). \bl{In a cylindrical plasma}, the synergistic effect on suppressing the RWM is investigated between this new damping mechanism and the plasma flow. An eigenmode formulation is derived based on magneto-hydrodynamic (MHD) theory, where the momentum equation is extended by including the turbulent viscosity term with a proportionality coefficient $\chi$. Numerical results show that, in the absence of plasma flow, increasing $\chi$ decreases the RWM growth rate but does not fully stabilize the mode. However, in the presence of sufficiently fast plasma flow, turbulent viscosity can lead to full suppression of the RWM, when $\chi$ exceeds a critical value. Similarly, at a given $\chi$ value, the plasma flow can fully suppress the mode when the flow velocity exceeds a threshold value. In particular, turbulent viscosity significantly reduces the threshold value of the flow velocity required for full stabilization of the RWM.

We present the development of a PET insert system for potential simultaneous PET/MR imaging using a 9.4 T small animal MRI scanner to test our system. The detectors of the system adopt a strip-line based multiplexing readout method for SiPM signals. In this readout, multiple SiPM outputs in a row share a common strip-line. The position information about a hit SiPM is encoded in the propagation time difference of the signals arriving at the two ends of the strip-line. The use of strip-lines allows us to place the data acquisition electronics remotely from the detector module to greatly simplify the design of the detector module and minimize the mutual electromagnetic interference. The prototype is comprised of 14 detector modules, each of which consists of an 8x4 LYSO scintillator array (each LYSO crystal is 3x3x10 mm(3)) coupled to two units of Hamamatsu MPPC arrays (4x4, 3.2 mm pitch) that are mounted on a strip-line board. On the strip-line board, outputs of the 32 SiPMs are routed to 2 strip-lines so that 16 SiPM signals share a strip-line. The detector modules are installed inside a plastic cylindrical supporting structure with an inner and outer diameter of 60 mm and 115 mm, respectively, to fit inside a Bruker BioSpec 9.4 Tesla MR scanner. The axial field of view of the prototype is 25.4 mm. The strip-lines were extended by using 5-meter cables to a sampling data acquisition (DAQ) board placed outside the magnet. The detectors were not shielded in the interest of investigating how they may affect and be affected by the MRI. Experimental tests were conducted to evaluate detection performance, and phantom and animal imaging were carried out to assess the spatial resolution and the MR compatibility of the PET insert. Initial results are encouraging and demonstrate that the prototype insert PET can potentially be used for PET/MR imaging if appropriate shielding will be implemented for minimizing the mutual interference between the PET and MRI systems.

The purpose of our study was to make a comparison between the fixation strength of optimum placed pedicle screw (OS) and re-directionally accurate placed pedicle screw (RS) after lateral pedicle breach.A total of 30 fresh lumbar vertebrae (L1-5) were gained from 6 male or female pigs weighing about 100 kg, which were divided into 2 groups according to different ways of pedicle screws placement: OS group (n=30) and RS group (n=30). MTS machine was employed to detect the screw loosening and axial pullout. We examined seating torque, screw-loosening force, the maximal torque and post-loosening axial pullout in each pedicle screw.Maximal insertion torque of OS was (111.6±8.4) N•cm and RS was (79.0±6.3) N•cm, which indicated a significant difference (Z=3.012, p=0.003). Seating torque of OS and RS were (85.9±5.6) N•cm and (60.3±4.8) N•cm separately, and the difference was statistically significant (Z=2.799, p=0.006). Screw loosening force of OS and RS were (75.9±7.0) N and (52.4±6.3) N respectively, and the difference was statistically significant (Z=2.652, p=0.003). Post-loosening axial pullout force of OS and RS were (328.5±11.3) N and (269.1±9.6) N separately, demonstrating that the difference was statistically significant (Z=2.865, p=0.004).RS placement is an alternative for remediation following a lateral wall breach evidenced by significantly decreased seating torque, screw loosening force, the maximal torque and post-loosening axial pullout compared with OS.

Free-hand technique is widely used in pedicle screw placement for lumbar spine and generally safe; however, screw malposition still occurs. To develop a novel multi-level drill guide template for pedicle screw placement in lumbar spine and evaluate its accuracy.Twelve lumbar cadaveric specimens were randomly allocated into guide template group (n=6) and free-hand group (n=6). Computed tomography (CT) scans were obtained for reconstruction of three-dimensional (3D) model of each lumbar vertebra, and further an individual guide template was designed. Then the templates and their corresponding vertebra were developed by rapid prototyping (RP) technology. With the guide of the templates, screws were inserted via mini-open Wiltse approach. The positions of the screws were assessed based on postoperative CT images.In total, 120 pedicle screws inserted (guide template group: n=60 vs. free-hand group: n=60). For all 30 vertebras in the guide template group, all pre-designed personalized drill guide templates can be fitted into the facet joints of each vertebra well. Furthermore, our results revealed a significant improvement for the guide template group in the accuracy rate (p=0.026).Armed with advantages of minimal invasion, enhanced accuracy and safety, the novel technique of multi-level drill guide template can be properly applied in pedicle screw placement for lumbar spine and promises to be a potential option in clinical application.

The regeneration process is a method for boronoxygen defects passivation by using heat and illumination, and its benefits have been demonstrated for efficiently reducing light induced degradation (LID) on P-type cells. It is widely used for solving LID issue on p-type PERC cells in recent year. In this paper, post-heating was used to understand the thermal influence on regenerated cells. Comparison between cell with and without regeneration process, the post-heating caused extra LID (2%) in regenerated cells is much higher than that (0.5%) in as-fired cells. The difference of extra LID between as-fired and regenerated cells indicates that the post-heating results in defect state transition from regenerated state to annealed state in regenerated cells. Based on this phenomenon, the LID test must take the impact of latent heat after regeneration process such as subsequent module process into consideration. Therefore, the regeneration process windows of temperature and light intensity need to be redefined when post-heating is introduced after regeneration process. The result of process window redefinition shows that the regeneration conditions of 1.4C suns light intensity can reduce the post-heating caused extra LID about 0.8% as compared with the regeneration conditions of 1C suns light intensity, and LID has no significant change as temperature of regeneration condition in a range from 225 °C to 275 °C. Additionally, cells with regeneration condition of 175 °C have low as regenerated efficiency, and the LID of cells with regeneration treatment at 300 °C is higher than that of cells treated with lower temperatures.

Photovoltaic (PV) power output forecasting is a crucial issue in the PV power industry and power company. Nevertheless, the disadvantage of the existing PV power output forecasting models is that they often ignore weather fluctuation and uncertain information between the irradiation and ambient temperature caused by moving cloud, which leads to short of forecasting accuracy. This paper is to present an improved radial basis function neural network structure (RBFNN) with multi- parameters forecasting scheme to overcome above drawbacks. Result of the case study acquired by the proposed scheme is compared with two typical artificial neural network forecasting methods including radial basis function neural network (RBFNN) and back propagation neural network (BPNN). It demonstrations that the proposed model leads to better precision for forecasting PV power output.

Osteoporosis (OP) is a kind of disease with a 25% incidence, characterized by the bone mass loss, bone microstructure damage, increased bone fragility, and easy fracture. miRNA plays an important regulatory role in the process of bone remodeling, especially in the regulation of differentiation and function of osteoblasts and osteoclasts, and the development and progression of OP and other bone diseases. In the future, it is expected to delay the bone loss and promote the bone remodeling via the overexpression or inhibition of specific miRNAs in specific tissues, thereby treating OP.

Our present study aimed to evaluate the effects of Wnt11 overexpression on the adipose-derived stem (ADSCs) cells differentiation to the nucleus pulposus (NP) cells and its function in the ADSCs cells growth, proliferation and induction of the NP cells markers.The cell growth was detected using the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) (MTT) assay and the cell cycle was assessed by the flow cytometry. The cells morphology was evaluated using the transmission electron microscopy. The transfection efficiencies of Wnt11 lentivirus were observed under fluorescence microscope. Besides, Quantitative Real-time PCR and Western blot analysis were applied to detect the relative mRNA and protein levels.Wnt11 lentivirus treatment could inhibit the ADSCs cells growth and arrest the cell cycle progression at the G0/G1 phase. Besides, the overexpression of Wnt11in ADSCs cells could induce the expression of the NP cells markers. Levels of SOX-9, aggrecan, and collagen type II were significantly increased in the ADSCs cells transfected with the Wnt11 lentivirus, in comparison with the untreated cells or the vector controls.The Wnt11 overexpression may provide some experimental evidence for the possible opportunity of the Wnt11 to promote the ADSCs cells differentiating to the NP cells. Therefore, the Wnt11 overexpression may have a potential utility for the treatment of the intervertebral disc degeneration.

In recent years, multiferroics have drawn much scientific attention in the field of spintronics due to the possibility of ‘zero-current’ manipulation of magnetization. In the present study, a three- dimensional phase field model was developed to investigate strain-mediated magnetoelectric coupling in FeGa/BaTiO 3 epitaxial bilayer systems. Due to strong elastic interaction, the spontaneous strain in a BaTiO 3 substrate can be efficiently transferred to the FeGa ferromagnetic thin film mounted on it, which resulted in printing of the domain patterns from the former to the latter. The transferred domain structures demonstrated high stability in response to the external magnetic field. Our simulation results showed that the magnetic domain wall motion can be manipulated using ultralow voltage of less than 0.08 V. Moreover, our investigation of the lateral size effects of the ferromagnetic layer demonstrated that the magnetic domain wall would not extinct even if the lateral size was reduced to tens of nanometer.

A novel tunable F–P linear filter used in optical fiber communication is reported in this paper. The filter consists of two fiber planes relative to the incident fiber and the outgoing optical fibers, and two fiber ends are, respectively, coated with reflective optical thin film. The F–P interferometric cavity improves the transmittance response characteristics of traditional F–P cavity and helps to improve the linearity and linear range. The optical thin film interference matrix analysis method on the transmission of the filter response is calculated and analyzed. The analyzed results show that the new linear filter has the advantages of good linearity, wide linear range and linear interval adjustable.

The flexoelectric effect which is defined as the coupling between strain gradient and polarization has long been neglected because it is insignificant in bulk ferroelectrics. However, at nanoscale, the strain gradient can be dramatically increased leading to giant flexoelectric effects. In the present study, the flexoelectric effects in epitaxial nano thin films of a 180° multi-domain structure, which are subjected to a compressive in-plane misfit strain, are investigated by the phase field method. Unlike the case of a single domain structure where the strain gradient is mainly attributed to the formation of dislocation which relaxes the misfit strain, in a multi-domain structure, it is attributed to many factors, such as surface and interface effects, misfit relaxation and domain wall structure. The results obtained show that relatively large flexoelectricity-induced electric fields are produced near the domain wall region. The induced field will not only influence the domain structure of the thin film, but also the hysteresis loops when it is under an applied electric field.

This paper examines microscale heat transfer from a heated thermal chip due to jet impingement. The jet issues from a micro slot nozzle, which has three different widths including 50 μm, 100 μm, and 200 μm, and impinges perpendicular to a small thermal chip (1.2 cm × 1.2 cm) that is heated uniformly. Both the nozzle and the thermal chip are made by the standard microfabrication techniques. Arrays of temperature sensors and heaters are made along the thermal chip by depositing polysilicon films with varying concentrations of boron on the Si wafer. Local heat transfer along the thermal chip under different sizes of jet impingement slots are measured. The heat transfer processes along the small thermal chip differ significantly from the case of large-scale macro jet impingement and are related to the flow structures reported previously near the wall. The value of the Nusselt number can be well correlated if the nozzle-to-plate spacing ratio is normalized using the breakdown length of the impinging jet.

Metamaterials and metasurfaces have demonstrated many unusual properties that are useful for creating high-performance terahertz devices and components. Integration of functional materials allows metasurfaces to expand their scope of applications. Here we show that hybrid metasurfaces can provide ultrafast modulation of terahertz waves that are critical for future applications in terahertz imaging and communications.

To determine the effects of adiponectin on high glucose induced BeWo cell proliferation in vitro.BeWo cells were seeded in 96-well plates at the appropriate density. After treatments with high glucose (25 mmol/L), western blot analysis of cyclin D1 and a colorimetric assay (cell counting kit-8, CCK-8) were used to analyse BeWo cells' proliferation, and western blot was used to detect the expression of adiponectin. Moreover, we added adiponectin (20 μg/ml) in the culture medium and three methods were utilized for cell proliferation analysis: CCK-8, cell cycle analysis (by flow cytometry) and proliferating cell nuclear antigen (PCNA) immunocytochemical staining.Compared to BeWo cells cultured by normal glucose and high mannitol, the proliferation of BeWo cells treated by high glucose increased (P0.05). Compared with BeWo cells cultured by high mannitol, the expression of adiponectin in BeWo cells treated by high glucose decreased. After added adiponectin in the culture medium, the proliferation of BeWo cells treated by adiponectin+high glucose decreased than that of cells treated by high glucose (0.770±0.050 versus 0.990±0.070, P0.05); the proportion of G2+S phases of BeWo cells treated by adiponectin+high glucose decreased than that of cells treated by high glucose [(40.7±2.1)% versus (44.9± 3.9)%, P0.05]; the rate of PCNA positive cell in BeWo cells treated by adiponectin+high glucose decreased than that of cells treated by high glucose [(28±5)% versus (44±5)%, P0.05].Adiponectin could inhibit proliferation of high glucose induced BeWo cells in vitro.

This paper concerns with the IVP for set differential equations involving causal operators with memory. By using the techniques of the measure of non-compactness, the existence of solutions has been established. The maximal and minimal solutions are obtained by means of Arzela-Ascoli Theorem.

In this paper, a bidirectional chaos secret communication system, based on mutually coupled semiconductor lasers (MCSLs) with asymmetrical bias currents, is proposed, and the synchronization characteristics and the communication performances of such a system are numerically investigated. The results show that the stable leader-laggard chaos synchronization can be achieved under relatively large asymmetrical bias current levels. Meantime, the influence of the intrinsic parameter variations of the laser on the synchronization quality is also considered, and the simulation reveals that this system still possesses good robustness to the parameter variations. Moreover, the influences of delay time and mutually coupling strength between the two lasers on chaos communication performance have also been discussed. Finally, unidirectional and bidirectional secret communication performances of such a system are examined under the chaos masking (CMS) encryption scheme, and the security of this system is also discussed.

This study used Finite Volume Method to simulate the magnetic profile of PVD (physical vapor deposition) chamber. For this longthrow PVD, the adaptor of the gap filling chamber has 120 mm height and 44 sets of side magnets around the adaptor. The polarity of the side magnets is the same as the top magnets of the chamber. These side magnets can very effectively increase electron mobility and collision frequency with sputtered atoms. The plasma simulation result shows that ionization rate on sputtered atoms can be up to 12% from such a PVD system along with such a magnet arrangement. Therefore, it shows a significant improvement on bottom side-wall coverage of via hole up to 45%. The deposition rate increases by 40%. In addition, the adjustment of RF bias and resputtering power can result in further improvement on 3/4 depth of side-wall coverage by 30% and corner step coverage by 70%. This study uses a simple method to apply 3DIC gap filling capability for an increase of aspect ratio (AR).

ThisstudyusedFiniteVolumeMethodtosimulatethemagneticprofileofPVD(physicalvapordeposition)chamber.Itcanbeapplied to different kinds of magnet arrangements to the longthrow sputtering PVD. For this long throw PVD, the best optimized process conditions and results from simulations included effects from chamber adaptor height, side magnet space, and magnet arangements. The side magnets consist of a total of 44 sets for one supporter around the chamber adaptor. Each set has three magnets. Each magnet has the magnetic field strength of 5,500 Gauss. The adaptor of gap filling chamber has a height of 120 mm and 44 sets of magnets around the adaptor. The polarity of side magnets is the same as the top magnets of the chamber. These magnets can very effectively increase of electron mobility and collision frequency with sputtered atoms. The plasma simulation result shows that the ionization rate on supttered atoms can be up to 26% from such a longthrow PVD system along with such magnets arrangement. Therefore, it shows a significant improvement on bottom side-wall step coverage in via hole up to 45%. The deposition rate increases by 40%. In addition, by adjusting RF bias and resputtering power, further improvement with 3/4 depth of side-wall step coverage by 30% and corner step coverage by 70% can be obtained. This study uses a simple method to apply to 3DIC gap filling capability for an increase of aspect ratio (AR). The improvement from this longthrow sputtering PVD with side magnets design around the adaptor not only results in low cost target design but also provides a very effective gap filling capability with higher deposition rate for 3DIC application. 3DIC (Three-dimensional Integrated Circuit) is a key technology for the semiconductor industry to keep up with Moore’s Law in the future. The semiconductor industry is always focusing on smaller and higher performing IC chips. In addition to widespread use of systemlevel packaging, lighter, greater signal transmission and less circuit interference devices are necessary, so 3DIC technology will be the main manufacturing technology for next generation products. 1‐3 By utilizingthethree-dimensionalTSV(Through-SiliconVia)technique, two-dimensional chips stack with each other in series that can achieve high-density and high-performance devices. This not only reduces power losses but also narrow the chip size. Following the smaller line width in devices and the increase in 3D stacking layers, this reduction of TSV width to less than one micrometer and increasing the TSV aspect ratio more than thirty appear to be the future trend. 4 There are increasingly more research topics about seed layer and barrier layer 4‐7 in TSV gap filling, and recent literature also focuses on how to use a strong magnetic field to fill high aspect ratio via in PVD processes. 6‐10 Moreover, recent studies have shown that the best magnet arrangements aiding and displaying to PVD process chamber can be received through simulation and analysis of the magnetic field. By aiding the magnets, the results showed an increase in plasma density and gas dissociation rate 11 in which a significant increase in the deposition rate from the sputtered atoms can be obtained. 11‐13 This work aims to create a simple and low cost way to increase the gapfilling capability and deposition rate of PVD equipment that can be applied to the semiconductor industry.

The strong correlations between the O/Zn ratio and carbon impurity incorporation have been observed on the ZnO films grown using N 2 O or O 2 as oxygen source in metal-organic chemical vapor deposition (MOCVD). From in-situ mass spectrometric measurements, the O/Zn ratio in the MOCVD reactor is found to decrease to a minimum value as the growth temperature increased till a critical growth temperature T c , and then increased above T c due to different dissociation rates of the oxygen and Zn sources. The strongest D and G modes, which are ascribed to carbon clusters sp 2 related modes, have been observed in Raman scattering spectroscopy for the ZnO samples grown at T c , indicating the highest incorporation rate of carbon impurity in the samples grown at T c . Compared with O 2 , N 2 O has a low dissociation rate and that leads to a lower value of O/Zn ratio, resulting in much stronger D and G modes and higher incorporation rate of carbon impurities in the samples grown at T c . It is interesting to note that the lowest specific resistances from Hall effect measurements were also obtained on the samples grown at T c , indicating possible electrical contributions from the formation of carbon clusters, which should be highly conductive regions in ZnO. Furthermore, ionization or addition of H 2 in the case of N 2 O can significantly enhance the dissociation of N 2 O, with film quality improved significantly. This study shows that a high O/Zn ratio is critical to suppress carbon impurity incorporation and to grow high quality ZnO by MOCVD, especially at low growth temperature.

Highly-pure iron powder was covered on porous silicon for fabricating semiconducting β-FeSi2 structures. X-ray diffraction and Raman scattering results confirm the formation of pure-phase β-FeSi2 after high-temperature annealing at 1100°C and then long-time persistence at 900°C. Scanning electron microscope observations reveal that large-size (>μm) β-FeSi2 grains mainly form in the pores of porous silicon and some nanocrystals grow on local surfaces. The temperature-dependent photoluminescence spectra disclose that the observed ∼1.54 μm emission arises from free exciton recombination, which is confirmed via the activation energy (0.25 eV) measurement. Our method provides a way to synthesize single-phase β-FeSi2 materials.

Solid tin oxide (SnO2) nanospheres were fab- ricated via one-step hydrothermal treatment of tin foil in aqueous alkaline solutions at 180°C. Based on the time- dependent experiments, the evolution behavior of Ost- wald ripening is proposed to explain the formation mech- anism. Besides a broad emission band at 600 nm, the SnO2 nanospheres, synthesized for 24 h, show an additional emis- sion band at 490 nm that has a great sensitivity to the con- tent of oxygen. Spectral examinations and analyses reveal that the two emission bands originate from the electronic states determined by the oxygen interstitials, intrinsic sur- face states, and oxygen vacancies.

Tin dioxide nanoribbons were fabricated for clarifying the origin of the red photoluminescence band. It is found that the red band abruptly decreases its intensity after annealing the nanoribbons in O2. The time-resolved photoluminescence decay curve shows that the red band has a luminescence lifetime of ns. The electron spin resonance spectrum discloses that the red band is related to a kind of combined oxygen-vacancy (V o + and V o ++ ) centers. Spectral analysis and theoretical calculation confirm that the red band arises from a transition between the combined oxygen-vacancy defect states in the band gap.

Vacancy structures in tin oxide nanoribbons fabricated via thermal evaporation and post-processing are probed by luminescence spectroscopy, and interesting properties that bode well for oxygen sensing are observed. Besides a broad 620-nm band, the fabricated tin oxide nanoribbons show a photoluminescence band at 480 nm when the measurement temperature is

Three kinds of silver nanostructures – nanowires, nanocubes and bipyramids – were synthesized via a simple solvothermal method by reducing silver nitrate with ethylene glycol using poly(vinylpyrrolidone) as an adsorption agent and adding different concentrations of sodium chloride (NaCl) into the solution. When a low-concentration NaCl solution is used, trace amounts of silver chloride (AgCl) appear and act as the seeds to facilitate the formation of the silver nanowires. However, when a high-concentration NaCl solution is used, large amounts of AgCl appear and mainly act as the controlling agent leading to the formation of silver nanocubes and bipyramids. Electron microscopy, X-ray diffraction and absorption spectra have been used to investigate the products, and a mechanism is proposed to interpret the morphological control of these structures. Our work provides a strategy to fabricate silver nanostructures with different shapes.

Self-assembled roselike ZnO nanostructures were synthesized via thermal evaporation of zinc powders without catalytic assistance at the relatively low temperature of 550 °C. The roselike structures consist of a large number of ZnO nanorods that uniformly arrange into hexagonal multilayers. The spontaneous nanoindentation effects under geometric constraints can be used to explain the structures. The cathodoluminescence spectra show a wide visible emission band related to Zn interstitials and oxygen vacancies. Field emission measurements demonstrate that the roselike ZnO nanostructures possess good electron emission characteristics with a turn-on field of 4.3 V/μm.