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The film growth mechanism of stoichiometric SiC in a chemical vapor deposition reaction system using methyltrichlorosilane (MTS) and hydrogen (H2) as the reactants was investigated. Kinetic analysis of the film growth rate profiles was performed in two distinct reactors, a hot-wall tubular reactor and a macrocavity reactor. Macrocavity experiments at 1273 K revealed that MTS reacts at the substrate surface with a low sticking probability of 2.1 × 10–6, while the film growth is primarily contributed by the gas-phase reaction of the reactants. Moreover, the tubular reactor exhibited a unique film growth rate profile, featured by an initial increase followed by a decrease along the gas flow direction. This observation strongly suggested a stepwise reaction in which MTS/H2reacts in the gas phase to form an intermediate species, which then contributes to film growth by reacting at the substrate surface. The apparent sticking probability of the gaseous intermediate species, derived from the best-fit surface reaction rate constant to the proposed stepwise reaction mechanism, was found to be approximately 1 × 10–3. The obtained sticking probability, being 3 orders of magnitude higher than that of MTS, indicated that the gaseous intermediate species may consist of a MTS/H2-derived active species that maintains the original Si–C bond structure, thereby leading to the stoichiometric SiC film growth.

C14H10BiKN2O10, triclinic, P1̄ (no. 2), a= 7.029(8) Å, b= 10.460(9) Å, c= 11.891(9) Å, α= 71.19(2)°, β= 80.57(3)°, γ= 85.18(4)°, V= 815.9(13) Å3, Rgt(F) = 0.0512, wRref(F2) = 0.1410, Z= 2, T= 296(2) K.

Background Ferroptosis is a novel type of regulated cell death and targeting ferroptosis may be a potential treatment strategy for lung cancer. Ziyuglycoside II (ZYG II) has a significant inhibitory effect on the growth of lung cancer cells. However, the selective anti-tumor effect of the ZYG II against lung cancer has not been systemically studied.Objectives We combined ferrostatin-1 and erastin to explore the potential therapeutic mechanism of the ZYG II for lung adenocarcinoma.Materials and Methods A549 and H1299 cells were randomly divided into the control, ZYG II, ferroptosis inhibitor group (ZYG II+ ferrostatin-1), and erastin group (ZYG II+ erastin). Cell proliferation was detected using the CCK-8 method. Cell migration and invasion were evaluated using the Transwell assay. The protein expression levels of Glutathione Peroxidase 4 (GPX4), Solute Carrier Family 7 Member 11 (SLC7A11), and Transferrin receptor 1 (TFR1) were measured using western blotting.Results Compared with the control group, the cell proliferation, migration, and invasion abilities of the ZYG II group significantly decreased, the protein expression levels of GPX4 and SLC7A11 in the ZYG II group declined significantly, and the expression of TFR1 increased significantly (p< 0.05). After adding ferrostatin 1 (ZYG II+ Ferrostatin 1), the cell proliferation, migration, and invasion abilities of the inhibited cells were significantly increased, the expression of GPX4 and SLC7A11 increased significantly and the expression of TFR1 decreased significantly (p< 0.05). However, after adding the erastin (ZYG II+ erastin), the cell viability was further inhibited in A549, the expression levels of GPX4 and SLC7A11 were further inhibited and the expression of TFR1 was further increased (p< 0.05).Conclusion ZYG II significantly inhibited the survival rate, proliferation, migration, and invasion ability of A549 and H1299 cells, possibly by inducing ferroptosis.

Two helical ligands (L1and L2) containing a pyridine-2,6-dicarboxamide skeleton were synthesized, and the crystal structures indicated racemic configurations with equal amounts of P- and M-helicity. Eight one-dimensional coordination polymers (CPs), {[ZnL1Cl2]·2CH3OH}n(1), [HgL1I2]n(2), {[AgL1NO3]·CHCl3}n(3), {[Cd(L1)2Cl2]·2DMF}n(4), {[Co(L1)2Cl2]·2DMF}n(5), {[ZnL2I2]·2DMF·H2O}n(6), [HgL2Cl2]n(7), and {[Hg2(L2)2Br4]·2CH3OH}n(8), were synthesized from the reaction of the two ligands with a series of transition metal ions. The crystal structures showed that the chiral self-assembly process of these ligands resulted in homochiral complexes (CP 1, 3, and 6), heterochiral complexes (CP 2, 4, 5, and 7), or the coexistence of homochiral and heterochiral complexes (CP 8). The gas adsorption/desorption experiments were investigated at room temperature, which showed that all the CPs exhibited good selective adsorption capacities (24.6–62.5 cm3/g) toward methanol vapor over other gas. Furthermore, CP 3, 5, and 6were selected for the recyclable methanol vapor adsorption experiments, and the results showed that all three CPs can be recycled as good adsorbents for methanol vapor.

Olivine compositions are widely used to constrain magmatic thermodynamic conditions such as magmatic temperature, oxygen fugacity, and H2O content. However, elemental diffusion may change the initial compositions and lead to large uncertainty on the estimation of these thermodynamic conditions. In this study, we conducted LA-ICP-MS elemental mapping and EPMA analysis of olivine phenocrysts and olivine-hosted spinel from the Jiagedaqi (JGD) alkaline basalts in northeast China to evaluate the influence of elemental difusion on olivine-composition-based geothermometry, oxybarometry, and hygrometry. The JGD olivines show normal Fo [Mg/(Mg + Fe) × 100 in moles] zoning, with cores having Fo of 77–87 and rims having Fo of 67–73. The constant P contents from core to rim indicate that these compositional zonings were caused mainly by difusion. Because Al is a slow-diffusing element and its content is relatively constant from core to rim, the temperature calculated by the Al-in-olivine thermometer is not influenced by elemental difusion and preserves the JGD olivine crystallization temperature up to 1150 °C. The temperatures calculated using the Sc/Y-in-olivine thermometer, the oxygen fugacity calculated using the olivine–spinel oxybarometer, and the H2O content calculated on the basis of Ca partitioning between olivine and melt are strongly influenced by the diffusion of Fo, Sc/Y, and Ca. However, the compositional plateaus in olivine cores, which were not influenced by elemental diffusion, preserve the magmatic temperature (1150 °C), oxygen fugacity (QFM+1.4), and H2O content (4 wt%) that applied during the formation of the JGD olivines. Together, these findings suggest that the mantle source of the JGD basalts was metasomatized by fluids released from the subducted slab. This study highlights that elemental difusion in olivine phenocrysts can strongly afect the application of olivine-composition-based geothermometers, oxybarometers, and hygrometers. However, primitive olivine cores that have not been influenced by difusion preserve the initial magmatic thermodynamic conditions.

Background: The tumor-specific immune responses, essential for removing residual lesions and preventing tumor metastases, can be stimulated by tumor-associated antigens (TAAs) released following photothermal therapy (PTT). However, due to the immunosuppressed microenvironment of pancreatic ductal adenocarcinoma (PDAC), the TAAs released by PTT are difficult to induce an effective immune response. In this work, we prepared the mesoporous silica (mSiO2) coated black titanium dioxide (bTiO2) photothermal nanoparticles (NPs) for enhanced photothermal-immunotherapy toward PDAC, in which resiquimod (R848) was loaded and DOTA-Gd was conjugated. The NPs are specified as bTiO2@mSiO2@Gd/R848 and abbreviated to NPs/R848. R848 as a kind of Toll-like receptor 7/8 agonist can remodel the tumor microenvironment (TME) in PDAC and induce a strong immune response. Furthermore, DOTA-Gd serves as a magnetic resonance imaging (MRI) contrast agent to improve the T1-weighted MRI performance of the NPs. Results: In vitro results of this study show that NPs/R848 could thermally ablate tumor cells and efficiently trigger dendritic cell (DC) maturation. The results of in vivo investigations demonstrate that the combined use of photothermal-immunotherapy exhibits a significant inhibitory effect on tumor growth. Besides, it promoted maturation of DCs and enhanced infiltration of CD8 + , CD4 + T cells to improve the TME in PDAC. Conclusions: Our study anticipates that by encouraging the maturation of DCs, this strategy will improve the TME and enable the successful photothermal-immunotherapy of PDAC.

Donald Black's theory 'The Behavior of Law' that the quantity of law varies with stratification, morphology, culture, organization and social control, is tested. The analyses yield very little support for Black's propositions except significant direct relationships between morphology and the quantity of five types of provincial laws.

Background: Methylenetetrahydrofolate reductase (MTHFR) 677C[right arrow]T polymorphism is heterogeneously distributed worldwide, with the highest and lowest frequencies of the T allele in Mexico and Africa, respectively, and a south-to-north gradient in Europe. Distribution of MTHFR 1298A[right arrow]C is less well known. It has been hypothesized that 677T frequency could result in part from gene-nutrient interactions. Objective: The objective was to compare the association of 677T and 1298C alleles with plasma concentrations of homocysteine, folate, and vitamin B-12 in geographical areas with contrasting 677T allele frequencies. Design: Healthy young adults (n = 1277) were recruited in Mexico City, the West African countries of Benin and Togo, France, and Sicily (Italy). Homocysteine, folate, and vitamin B-12 were measured in plasma, and MTHFR polymorphisms were measured in genomic DNA. Results: Mexico City and Sicily reported the highest and Benin and Togo reported the lowest plasma concentrations of folate. Mexico City had the highest 677T allele prevalence and the lowest influence of 677TT genotype on homocysteine, whereas the opposite was observed in Africa. The prevalence of the 1298C allele was lowest in the Mexicans and Africans and highest in the French. The percentage of the 677T genotype was significantly associated with the folate concentrations in 677CC carders in a univariate analysis (R = 0.976; 95% CI: 0.797, 0.996; P < 0.0002) and in a multiple regression model that included homocysteine, vitamin B-12, and age (P = 0.0002). Conclusion: Our data agree with the hypothesis of a gene-nutrient interaction between MTHFR 677C[right arrow]T polymorphism and folate status that may confer a selective advantage of TT-homozygous genotype when dietary intake of folate is adequate, at least in the areas studied. KEY WORDS Methylenetetrahydrofolate reductase, polymorphism, folate, homocysteine, vitamin B-12

ABSTRACTRotaviruses (RVs) are the leading cause of acute gastroenteritis in children, while histo-blood group antigens (HBGAs) are believed to be host attachment and susceptibility factors of RVs. A large case–control study nested in a population-based diarrhea surveillance targeting children <5 y of age was performed in rural Hebei province, north China. Saliva and serum samples were collected from all participants to determine HBGA phenotyping, FUT2mutations, and RV IgG antibody titers. A logistic model was employed to assess the association between host HBGA secretor status and risk of RV infection. Among 235 RV cases and 680 non-diarrhea controls studied, 82.4% of participants were IgG positive by an average age of 77 months. Out of the 235 RV cases, 216 (91.9%) were secretors, whereas the secretor rate was 76.3% in the non-diarrhea controls, resulted in an adjusted OR of 3.0 (95%CI: 1.9–4.7, P< .0001) between the two groups. Our population-based case–control study indicated a strong association between host HBGA secretor status and risk of RV infection in Chinese children. The high prevalence of Lewis-positive secretor status strongly suggests that Chinese children may be genetically susceptible to current co-circulating RV strains, and thus, a universal childhood immunization program against RV disease should be successful in China.

The protein hormone insulin exists in various oligomeric forms, and a key step in binding its cellular receptor is dissociation of the dimer. This dissociation process and its corresponding association process have come to serve as paradigms of coupled (un)folding and (un)binding more generally. Despite its fundamental and practical importance, the mechanism of insulin dimer dissociation remains poorly understood. Here, we use molecular dynamics simulations, leveraging recent developments in umbrella sampling, to characterize the energetic and structural features of dissociation in unprecedented detail. We find that the dissociation is inherently multipathway with limiting behaviors corresponding to conformational selection and induced fit, the two prototypical mechanisms of coupled folding and binding. Along one limiting path, the dissociation leads to detachment of the C-terminal segment of the insulin B chain from the protein core, a feature believed to be essential for receptor binding. We simulate IR spectroscopy experiments to aid in interpreting current experiments and identify sites where isotopic labeling can be most effective for distinguishing the contributions of the limiting mechanisms.

Online consumers have their own risk perception known as perceived risks. If consumers detected a variety of risks with the online purchase, consequently it will decrease the intention to shop online. The purpose of this paper is to examine the relationships between online store image towards perceived risks (financial, product-performance, time, delivery, psychological, privacy, social, and after-sale risks) and the relationship between perceived risks towards online purchasing behaviour. Data collected from 330 respondents who have experience in online purchasing suggested that online store images have influence financial, product-performance, time, psychological, social, and after-sale risks. Surprisingly, online store image has no effect on privacy and delivery risks. Meanwhile, financial, psychological, social and after-sale risks have influence on online purchasing behaviour. In other words, increased risk in product performance, financial, psychological and after-sale risks influence the online purchasing behaviour by reducing the intention to purchase the product. Therefore, online purchase platform providers, online retailers and online marketers should identify the online store image that is capable to reduce consumers' perceived risks thus leading to a positive purchasing behaviour. Additionally, consumers can gain knowledge about the risks that might be faced during online shopping activities.

To investigate the diffusion of carbon in the iron sheet during gas–solid decarburization in a weak oxidative atmosphere (Ar + H2+ H2O), the microstructures of iron sheets following decarburization were observed through SEM. The carbon gradient following decarburization in the iron sheet along the thickness direction was detected in this study. The results showed that the iron sheet along the thickness direction following decarburization consisted of three layers: the L1layer (ferrite phase) that was near the surface, the L2layer (cementite phase) that was between the L1+ L3 layers, and the L3layer (cementite + ferrite + graphite phase) that was in the center of the sample. The depth of the decarburization layer (L1+ L2) showed a good linear relation with the square root of the decarburization time. The carbon gradient in iron sheet along the thickness direction was of ladder type during decarburization. The carbon content in the center of iron sheet was influenced by the decarburization time or the temperature. The carbon migration in iron sheet consisted of stable carbon decomposition and free carbon diffusion. The carbon migration in the S2stage of iron sheet was the controlling step of the entire decarburization process.

ABSTRACTMacroautophagy/autophagy is vital for intracellular quality control and homeostasis. Therefore, careful regulation of autophagy is very important. In the past 10 years, a number of studies have reported that estrogenic effectors affect autophagy. However, some results, especially those regarding the modulatory effect of 17β-estradiol (E2) on autophagy seem inconsistent. Moreover, several clinical trials are already in place combining both autophagy inducers and autophagy inhibitors with endocrine therapies for breast cancer. Not all patients experience benefit, which further confuses and complicates our understanding of the main effects of autophagy in estrogen-related cancer. In view of the importance of the crosstalk between estrogen signaling and autophagy, this review summarizes the estrogenic effectors reported to affect autophagy, subcellular distribution and translocation of estrogen receptors, autophagy-targeted transcription factors (TFs), miRNAs, and histone modifications regulated by E2. Upon stimulation with estrogen, there will always be opposing functional actions, which might occur between different receptors, receptors on TFs, TFs on autophagy genes, or even histone modifications on transcription. The huge signaling network downstream of estrogen can promote autophagy and reduce overstimulated autophagy at the same time, which allows autophagy to be regulated by estrogen in a restricted range. To help understand how the estrogenic regulation of autophagy affects cell fate, a hypothetical model is presented here. Finally, we discuss some exciting new directions in the field. We hope this might help to better understand the multiple associations between estrogen and autophagy, the pathogenic mechanisms of many estrogen-related diseases, and to design novel and efficacious therapeutics.Abbreviations:AP-1, activator protein-1; HATs, histone acetyltransferases; HDAC, histone deacetylases; HOTAIR, HOX transcript antisense RNA

Repeat masked phrap with scaffolding (RePS) identifies exact 20 mer repeats from the shotgun data and removes them before assembly. The real data for human and rice that reasonable assemblies are possible even at various coverages.

Here, Boisclair Lachance et al. investigate how the cis-regulatory logic of a tissue-specific cis-regulatory module (CRM) responsible for even-skipped(eve) induction during cardiogenesis organizes the competing inputs of two ETS members: the activator Pointed (Pnt) and the repressor Yan. Their findings provide insight into a novel mechanism by which differential interpretation of CRM syntax by a competing repressor–activator pair can confer both specificity and robustness to developmental transitions.

The North China Craton (NCC) is believed to be the best example of cratonic destruction. However, the processes leading to cratonic destruction remain unclear, largely due to a lack of knowledge of the nature of the Mesozoic NCC lithospheric mantle. Here we report new petrological and geochemical data for Early Cretaceous NCC basalts, which provide insights into the nature of the underlying lithospheric mantle. The Early Cretaceous basalts (all tholeiites) show a limited variation in geochemical composition. In contrast, olivine-hosted melt inclusions from these basalts display a wide range in compositional variation and include both alkalic and tholeiitic basaltic compositions. This result provides the direct evidence of the contribution of silica-undersaturated alkali basaltic melts in the petrogenesis of the Early Cretaceous NCC basalts. In addition, the compositions of olivine phenocrysts and reconstructed primary melts indicate that the Early Cretaceous basalts are derived from a mixed peridotite and refertilized peridotite source. The Pb isotopic compositions of melt inclusions in high fugacity of oxygen (fo) olivines combined with trace element characteristics of these basalts reveal that heterogeneous lithospheric mantle sources for Early Cretaceous basalts were metasomatized by carbonate-bearing eclogite-derived melts. The Pb isotopic variations of the melt inclusions and clinopyroxene and plagioclase phenocrysts demonstrate that the mantle-derived magmas were variably contaminated by lower continental crust. We propose that multiple subduction events during the Phanerozoic, combined with mantle-plume activity, likely play a vital role in the generation of the Early Cretaceous voluminous magmatism and cratonic destruction. Reporting first in situ Pb isotopic data for olivine-hosted melt inclusions in the Early Cretacous basaltsProviding direct evidence for crustal contamination in the generation of Early Cretaceous mafic rocksMetasomatic weakening, the plume impact, and subduction of Pacific slab play a crucial role in cratonic destruction

A facile synthesis method of three dimensional reduced graphene oxide (RGO)/multiwalled carbon nanotubes (MWCNTs) hydrogel was introduced. Hydrogel samples which were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM) and examined by X-ray diffraction (XRD) have been used as the electrode of supercapacitor. Cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) were used to investigate the Supercapacitors which we have fabricated. Because MWCNTs inserting into layers of RGO homogeneously prevent the layers of RGO from stacking and enlarge the specific surface area of graphene, the specific capacitance of RGO/MWCNTs material has been greatly improved. At the current density of 0.2A/g, the specific capacitance of RGO/MWCNTs electrode is about 176F/g, which means a 52% increasement compared to which of pure RGO material electrode. And the specific capacitance of RGO/MWCNTs also achieves a good rate property.

Deformation twinning, i.e., twin nucleation and twin growth (or twin boundary migration, TBM) activated by impinged basal slip at a symmetrical tilt grain boundary in HCP Mg, was examined with molecular dynamics (MD) simulations. The results show that the -type twinning acts as the most preferential mode of twinning. Once such twins are formed, they are almost ready to grow. The TBM of such twins is led by pure atomic shuffling events. A secondary mode of twinning can also occur in our simulations. The twinning is observed at 10 K as the secondary twin. This secondary mode of twinning shows different energy barriers for nucleation as well as for growth compared with the -type twining. In particular, TBMs in this case is triggered intrinsically by pyramidal slip at its twin boundary.

Contract phone card is a kind of special product with follow-up service. For this particular product, we designed a revenue sharing contract for communication operator, based on a research of product pricing and ordering problem about communication operator and its sales agent. The contract will encourage the sales agent to improve the quantity of cards and achieve the purpose of increasing the number of users, by sharing a certain proportion of fixed subsequent earnings to the sales agent. Then, we used CVaR risk measurement tools to study pricing and ordering problem of sales agent in the revenue sharing contract. The results show that appropriate sharing factor could achieve the optimal coordination between communication operator and its tier-one agent, and maximize the benefit of the supply chain.

Sequencing Batch Reactor (SBR) wastewater treatment process has lots of characteristics, such as randomness, time-varying characteristics, complexity and so on. In order to solve the above problems, a predictive PID control method based on DMC and ordinary PID for SBR wastewater treatment process dissolved oxygen (DO) control was proposed. The simulation studies were conducted with the MATLAB in a sewage treatment plant. The results showed that the proposed predictive PID control method was robust and jamproof. Meanwhile, the wastewater treatment system also had a strong capacity of shock load.

To compare the light-scattering effectiveness of surface-textured solar cells of various design parameters such as density, diameter, refractive index, and location, this study used a new parameter, optical path length gain (OPLG), that is more sensitive than Haze. By modeling two-dimensional disordered textures as a structure that comprises many randomly distributed, small, spherical scatterers, ray-tracing simulations of surface-textured thin-film silicon solar cells were performed. The simulation results suggest that: (1) the optimal scatterer diameter for hydrogenated amorphous silicon (a-Si:H) solar cells is ∼50  nm, producing an average OPLG of 3.5; and (2) the optimal scatterer diameter for a-Si:H/μc-Si:H (hydrogenated microcrystalline silicon) tandem cells is ∼75  nm, producing an average OPLG of 3.4 and an increase in the bandwidth of the absorption spectrum of 14.5%.

Ionic liquid containing alanine cations and hydrogen sulfate was synthesized using alanine and sulfuric acid as materials. Fourier Transform Infrared Specctrometer was used to verify the final product. The results showed that the objective product was developed successfully. General properties of the final product were detected. The results showed that strong acidity, large viscosity, soluble in polar solvents and insoluble in nonpolar solvents were the products properties which were suitable for liquefying. The liquefaction rate of ionic liquid on pine was studied. Study the optimum liquefaction condition using the method of orthogonal experiment design. By stirring at 120°C for 2 hours using ionic liquid with the concentration of 80% and with the mass ratio of 30, liquefaction rate of ionic liquid on pine was high.

The light scattering properties of the dent nanoparticles upon wafers is discussed in this paper. Taking the advantage of the Bobbert-Vlieger (BV) theorem, the scattering model between wafer and dent nanoparticles is established. The scattering process is analyzed and the scattering coefficients are derived by using of the vector spherical harmonic function. The differential scattering cross section (DSCS) of the dent nanoparticles upon the wafer is calculated which is compared with the extended Mie method proved the validity of the method and the influences of the dent position, dent scale and scattering angle on the DSCS are analyzed numerically in details. The result is shown that the effect of the dielectric is smaller than the metal. Therefore, the material of the defect and the shape can be extracted by calculate the DSCS, which provide strong theoretical foundation to the nondestructive detector engineer.

In combination with field blasting vibration tests in Daiyuling 2# Tunnel, abundant field monitoring datum have been obtained, in order to predict the strength of blasting vibration and research the control problem about stability of surrounding rock. Through the evaluation on blasting affects of the first excavated tunnel when the last excavated tunnel in the initial stage is into tunnel hole, establish the relationship of blasting vibration disturbing degree both neighborhood tunnels to improve the accuracy. Acoustic testing technology has been adapted to test rock acoustic velocity with blasting from beginning to end. The experimental results show that: (1) rock has a larger effect on attenuation effect in the spread of seismic wave, and blasting is really damage the surrounding rock; (2) regression analysis with the formula reflecting correctly the real situation on the blasting stress wave attenuation; (3) compared with blasting vibration attenuation coefficient both the left tunnel and right tunnel, the blasting vibration damage in soft rock is more than in hard rock; (4) the most dangerous location caused by tunnel blasting excavation is the adjacent tunnel blasting face, and its velocity is 5.8845 cm/s, it is practical and feasible that the clear distance of neighborhood tunnels should keep in 21m.

In order to improve the calculation speed and precision of the linear guide precision straightening stroke algorithm, a novel way to predict straightening stroke is proposed based on springback control theory. The relationships between straightening springback control and straightening stroke have been constructed by having analyzed on the curvature changes of the straightening process. The straightening stroke prediction quick algorithm has been designed and applied in straightening experimental. After comparison on the stroke-deflection model and experimental, it is proved that the springback control model can improve the speed and real-time of straightening stroke prediction and calculation and have good adaptive capacity in a large bending condition.

The issue about choosing the point of interconnection is important to reduce the impact of Photovoltaic generation to the power grid security and investment. Here we present a model to identify the optimal point of Photovoltaic generation interconnection, based on the identification method of the critical elements in the complex network theory. In the model, the critical threshold is used as the measure index which reflects the minimum capacity of power grid to maintain every element stable operation. The simulations are carried out in the IEEE-118 power system, the IEEE-145 power system and the IEEE-162 power system, and the results show that the nodes with relative large electrical betweenness are good choice of the Photovoltaic generation interconnection points and the generation nodes are better choices compared to the transmission nodes. The work may have a certain guiding significance for the selection of Photovoltaic generation interconnection point and the planning of power system.

We have studies of the changes in the surface states of carbonized Si(111) substrates treated under various temperature programs prior to high-temperature 3C-SiC film growth in a low pressure chemical vapor deposition system using SiH4, C2H2, and H2as reactant gases. The carbonized Si surface underwent a change in bonding from SiC to disordered graphite, together with the formation of etch pits, when heated directly from the carbonization temperature of 1343 K to the growth temperature of 1523 K under a H2flow over a period of 5 min; this transformation deteriorated the quality of the subsequent 3C-SiC growth. In contrast, a void-free stoichiometric SiC surface was preserved when we inserted a rapid cooling step, to near room temperature, under a H2flow of 352 sccm within a period of 15 min after shutting off the C2H2gas flow at the end of the surface carbonization process. The sharp temperature decrease in this program sealed off the carbonized substrate surface and, thus, led to a high film quality for subsequent 3C-SiC(111) growth.

Chose high-chromium cast iron as the material to make the mud pump shell, the composition of high-chromium alloy has been optimized and five kinds of alloy ( A, B, C, D and E) are designed. Furthermore, using the heat treatment method of air-cooled quenching of 1040°C + 260°C tempering, the relationship among material hardness, the impact toughness and the heating temperature is analyzed after heat treatment. Finally, the abrasion performance of wear-resistant materials is tested. The test result shows that all kinds of wear-resistant materials display well anti-abrasion performance, where the material E has the best relative wear resistance and 19.3% higher than the imported pump casing material. The results provide a scientific standard for selecting the practical wear-resistant materials and locating the piece casting bivalve pump of Cr26 high-chromium cast iron.

Pipe drainage system is used mostly on urban area, but under the pressure of the rapid urbanization, the disadvantages of traditional pipe drainage system are more and more serious. Analyzed the urban rain flood utilization situation in China and foreign countries, and main problems of traditional pipe drainage system in China, the key technology of comprehensive utilization for urban rain flood is put forward, which contains the multi-function tunnel building based on the concave green fields constructing, permeable bricks laying, reservoir constructing for rain flood collecting. This method can effectively prevent the drought or flood disaster due to inadequate or extensive rain volume and can make full use of rain flood resources too.

in the River, velocities of surface water flow typically are larger than the near-bottom flow. Combined with background of artificial disturbance sediment, surface water flows is taken to the river bottom to loose and raise sediment, dredge and so as to achieve the purpose of slowing river siltation. Preliminary tests showed that using low-power diversion disturbing sand dredging system, flow velocity of disturbing nozzle is larger than the incipient velocity of sediment, and the purpose of disturbing sediment and sediment transport can be obtained.

As the installed capacity of photovoltaic power station is growing, the power prediction techonology is of great important to reduce the random damage to the power system. A prediction model using neural network is proposed in the paper, the solar radiation model is adopt to ensure the accuracy of the prediction results in clear sky contions.Through the analysis of photovoltaic power station output power influence factors, the the solar radiation intensity, humidity and temperature are chosen as the input of the neural network prediction model.At the same time, in order to improve accuracy the photovoltaic power station power prediction model, the power adopt numerical weather forecast information. And the prediction model is tested by the photovoltaic power station historical operation data, and the short-term power prediction has a good performance.

Cavity walls structure is unsuitable in cold area for its faultiness of poor heat-insulating property. But the cavity walls constraint masonry construction is suitable in cold area for its high heat-insulating property. Studies are carried as setting up the restoring force model of the cavity walls confined masonry structure and analyzing the dynamic time-history of cavity walls constraint masonry structure under 7 degrees small earthquake, middle earthquake or large earthquake through EL centro wave, TALF wave, Ninghe wave and Qian'an wave, which indicates that cavity walls constraint masonry construction can satisfy seismic demand of 7 degree quake. Finally, the formula for calculating the interlayer displacement of cavity walls confined masonry structure near collapse is put forward and the counting result is compared with that of dynamic time-history analyzing, which shows that the accuracy of this formula is high enough to be used for analyzing the seismic performance of cavity walls constraint masonry structure. Foundation projects: Special Basic Scientific Research for Central Public Institute (2008B002, 2010A04), Open Fund of Key Laboratory of State Education Ministroy on Urben and Engineering Safe and Disaster Diminish & Key Laboratory of Beijing on Engineering Seismic and Treatment (EESR2010-07), and High Level Talent Support Project of Heilongjiang University (HDTD2010-13).

Focusing on the dredging problem in Yellow River irrigation district, the whip-impact sediment dredging technology is put forward in the Xingjiadu Irrigation District. The finite element model of dredging process is built and the flow characteristic and behavior under design condition is studied, which can provide a theoretical basis for the feasibility of the whip-impact sediment dredging technology. Also, it can provide effective measures for the improvement of sediment dredging effects and whip-impact equipments.

This paper is used by the combined test technology of resistivity composite profile and high-density resistivity method. Regard Daiyuling the first tunnel engineering geology survey work area as a test site. Different physical parameters such as resistivity composite profile curve of transverse sectionⅠ~Ⅳ line and vertical profile and measured, fitting apparent resistivity quasi section measured by high-density resistivity method reflect geological phenomenon. Through mutual contrast verification, improve the accuracy and reliability of survey results. Provide necessary geophysical basis for engineering geological exploration.

Array induction logging tools (AILT) detects the stratum conductivity based on the principle of electromagnetic induction, as a result, the signal of the amplitude using the AILT is in microvolt level. The small-signal is always drowned by noise at high-temperature and high-pressure condition. In order to collect the weak signal accurately, we propose a design method of signal modulator circuits based on the principle of differential amplifier and active band-pass filter with second band limitless gain and multi-path negative feedback. First, make the induction signal obtained from the coil two stages amplification. Then Execute two-order band-pass filter to the enlarged signal. At last, process the filtered signal by the backward circuits. Simulating the circuits by Pspice16.3, The result of simulation indicated that the gain relative error of preamplifier is less than 1% and the center frequency relative error of band filter is less than 4%. These data suggest that the relative error of the design circuits is less than routine instrument by 5%. So the Simulation verifies the feasibility of the signal modulator circuit.

To solve the early destruction problems occurred when overlaying asphalt pavement structure containing semi-rigid base on broken cement concrete pavement, finite element software is used to compare the stress characters between the repaving pavement and ordinary pavement, and analyze the repaving structures under different loads and different road transverse grade. It shows that the value of compressive stress at the top of base of repaving pavement is significantly higher than that of ordinary pavement, meanwhile, its value of tensile stress of base bottom is lower; the asphalt surface and new base top of repaving pavement need to bare a high value of shear stress and compressive stress under overload, so it’s prone to splitting failure in the base. With the increase of transverse grade, both the shear stress difference of road surface and maximum vertical compressive at top of the base increase in a lower position, but the situation is opposite in the higher position.

The compactness is prone to markedly decreased after dampening in the subgrade filled by Ginger-stone soil. To solve this problem, a series of tests have been done on the conventional and improved Ginger-stone soil, such as granule analysis test, compaction test, CBR test and water stability test. The test results indicates that the CBR value of Ginger-stone soil is low and it has a strong capillary action, which make it cannot be directly used for roadbed filling of expressway and first class highway. By adding the lime(3%) and fly ash (9%) into the Ginger-stone soil, the CBR value and water stability of sample are obviously improved, and its control of construction becomes easy, so the improved Ginger-stone soil can be directly used as roadbed filling.

Liquefactions have been carried out on plantation fir scrap, with allylimidazolium ionic liquids as liquefaction agent. The primary component of plantation fir was analyzed, fir scrap properties were tested in contrast to peeled fir. Single-factor experiments were employed to discuss the influential factors liquefying plantation fir scrap by ionic liquids. The results showed that the appropriate conditions of liquefaction were 80℃, 30min, and the ratio of wood to liquor was 7:1, in these conditions, the liquefaction is nearly complete.

A MDI-based waterborne polyurethane emulsion(PU) was synthesized by the reaction of polyester glycol(PBA), di-methylol propionic acid(DMPA) with 4,4`-diphenylmethane diisocyanate (MDI) instead of toluene di-isocyanatotoluene(TDI) because of its low toxicity, low saturated vapor pressure. The factors influencing the properties of waterborne polyurethane emulsion were discussed. It was observed that the appearance and properties of the PU emulsion were nearly related with the ratio of NCO/OH(R) and the amount of DMPA.

Ionic liquid containing L-alanine cations and hydrogen sulfate was synthesized using L-alanine and sulfuric acid as materials. Fourier Transform Infrared Specctrometer was used to verify the final product. The results showed that the objective product was developed successfully. General properties of the final product were detected. The results showed that strong acidity, large viscosity, soluble in polar solvents and insoluble in nonpolar solvents were the product’s properties which were suitable for liquefying. The liquefaction rate of ionic liquid on paper was studied. Study the optimum liquefaction condition using the method of orthogonal experiment design. By stirring at 80℃ for 3 hours using ionic liquid with the concentration of 100%, liquefaction rate of ionic liquid on paper was high.

Recent ground-breaking experiments studying the effects of spin polarization on pairing in unitary Fermi gases encountered mutual qualitative and quantitative discrepancies which seem to be a function of the confining geometry. Using numerical algorithms we study the solution space for a three-dimensional fully self-consistent formulation of realistic systems with up to 105 atoms. A study of the three types of solutions obtained demonstrates a tendency toward metastability as the confining geometry is elongated. One of these solutions, which is consistent with Rice experiments at high trap aspect ratio, supports a state strikingly similar to the long sought Fulde-Ferrel-Larkin-Ovchinnikov state. Our study helps to resolve the long-standing controversy concerning the discrepancies between the findings from two different experimental groups and highlights the versatility of actual-size numerical calculations for investigating inhomogeneous fermionic superfluids. [ABSTRACT FROM AUTHOR]

AbstractUnderwater sensor networks (UWSN) for long-term ocean monitoring become hot spots in recent research, but the unique characteristics of underwater acoustic channel bring challenges in medium access control (MAC) protocol design. Most existing approaches are simplex and cannot suit well for all network load cases. We propose HCR, a high efficient MAC protocol for UWSN, which combines the excellences of competition-based and scheme-based protocols, and can suit for all traffic load cases. HCR is a hybrid of TDMA and a random access protocol, and protocols switch dynamically due to the change of traffic load. It is load adaptive, energy efficient and has high network throughput. Some trade-offs and optimization problems are also discussed. Finally, detailed simulations are made to validate the capability and efficiency of HCR.