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The concrete-filled double steel tube (CFDST) has been more and more widely used in infrastructure due to its greater moment of inertia compared to the ordinary concrete-filled steel tube (CFST). With the increase in collision accidents occurring in recent years, the research on CFDST under impact needs more attention. To study the dynamic responses of CFDST columns under lateral impact, the finite element package ABAQUS was used to simulate the impact force and mid-span deflection of the column under the coupling action of axial force and lateral impact based on the comparison of experimental data in the literature. The influence of hollow ratio, axial compression ratio, slenderness ratio, impact energy, and material strength on the dynamic responses of the CFDST column are studied. The results show that with the increase in the hollow ratio from 0.3 to 0.8, the residual mid-span deflection of the CFDST column decreases by 77.9%. The mid-span deflection shows an increasing trend following a decreasing one with the axial compression ratio increasing. With the increase in the slenderness ratio from 30 to 60, the plateau impact force decreases by 62.5%, and the residual mid-span deflection increases by 240.5%. The practical formulas for the impact-bearing capacity and residual mid-span deflection of the CFDST column are suggested with high accuracy.

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), is a destructive wheat pest worldwide and an important alien species in China. Based on 258 distribution records and nine environmental factors of the Hessian fly, we predicted the potential distribution area in China under three current and future (2050s and 2070s) climate change scenarios (RCP2.6, RCP4.5, and RCP8.5) via the optimized MaxEnt model. Under the current climate conditions, the suitable distribution areas of the Hessian fly in China were 25–48° N, 81–123° E, and the total highly suitable distribution area is approximately 9.63 × 105 km2, accounting for 9.99% of the total national area. The highly suitable areas are mainly located in northern Xinjiang and central and eastern China. With the rising global temperatures, except for the high-suitable areas under the RCP8.5 scenario, most potential geographic distribution areas would expand in the future. The minimum temperature in February (tmin-2), precipitation in March (prec-3), maximum temperature in November (tmax-11), and precipitation seasonality (bio-15) are important factors that affect the potential geographic distribution of the Hessian fly. This study provides an important reference and empirical basis for management of the Hessian fly in the future.

In order to study the dynamic behaviour and energy dissipation of reinforced recycled aggregate concrete (RAC) beams under impact, four groups of reinforced RAC simply supported beams with various recycled coarse aggregate (RCA) replacement percentages are designed and tested under drop weight impact at the mid-span of beams and corresponding another four groups of beam specimens under static loading. The static resistance versus mid-span displacement curves are obtained from static loading test to analyse the effect of RCA replacement percentage on the beam's mechanical performance. It is concluded that the static resistance and stiffness of the RAC beam decrease slightly as the RCA replacement percentage increases and the deformation curve of reinforced RAC beam conforms to the classical bending theory of beam. In the drop weight impact test, the reinforced RAC beams failed with both global and local damage, and in bending controlled mode. The time history of impact forces, mid-span displacements and stress states of the beams are investigated. The mid-span displacement of the beams increases with the increase of RCA replacement percentage. The energy dissipation of the beams under impact is discussed based on the simplified resistance model. A concept of global damage energy dissipation is introduced and the method for calculating the global damage energy dissipation of the reinforced RAC beam under impact is proposed. The global damage energy dissipation ratio is defined and used to measure the proportion of global damage and local damage on reinforced RAC beam under impact. The experimental results presented here provide benchmark data for the further research work on the dynamic response of reinforced RAC beam under impact.

Planet-Gear reducer with high integration has been widely applied to various fields. Because of smaller size and using frequently, the sun gear is the most vulnerable part of the planetary gear reducer. In this paper, we do some research about a planetary reducer used in a rotating platform. The actual working input torque of the reducer is tested by MPU6050 acceleration sensor and STM32F1 microcontroller. Based on the torque, we analyze the structure of reducer and check the contact strength of tooth surface and bending strength of sun gear in the second-stage of reducer. The checking results show that the strength of the sun gear can meet the design requirements even under the worst working conditions. At last, according to the checking result, the optimization suggestions are put forward for the motor control, which can extend the service life of the reducer without affecting the use requirements.

A two-degree-of-freedom mass-spring model considering the local effect of the contact component is developed to investigate the dynamic responses of reinforced concrete beams under low-velocity impact actions. The local modified coefficient is proposed by parameter regression from drop-hammer impact test results, and then the simplified model is validated by other relevant research. As shown, the simplified model is able to capture the dynamic responses of reinforced concrete beams. In addition, the impact process is simulated and further analysed. The effects of initial impact velocity and the yield criterion of reinforced-concrete beams are investigated. The energy dissipation levels for various cases with the same initial impact energy are compared. An analysis proposal is also developed to predict the dynamic responses of reinforced concrete beams if the impact action case is uncertain.

Xanthomonas albilineans (Ashby) Dowson (Xa) has devastating consequences on the vascular system of sugarcane plants and causes severe yield loss in sugarcane. In addition, the incubation period of the pathogen is long, and some infected varieties may remain symptomless for months and even years, leading to the spread of this pathogen over a large area. Therefore, it is important to establish a reliable and economical detection method for Xa. Based on the whole genome sequences of Xa, the hrpB gene was used to design 10 pairs of primers for the establishment of a novel qualitative PCR protocol. These pairs of primers were tested by species-specificity, annealing temperature, primer concentration and sensitivity. The most suitable hrp-10 primer pairs were chosen and used to detect the pathogen with assay sensitivity allowing the detection of 102 copies/μL of Xa purified DNA in suspension cultures. Moreover, sixty-eight sugarcane accessions (including 40 cultivars and 28 wild germplasms) with suspected infection by Xa from five provinces of China (Fujian, Yunnan, Hainan, Guangxi and Guangdong) were detected by the hrp-10 primer pairs. The results showed that the detection rate of the pathogen was 75% for symptomatic accessions, and 14% for asymptomatic samples. This newly developed PCR protocol provides a reliable and relatively inexpensive tool for the detection and identification of the pathogen Xa from infected sugarcane leaf.

In this paper, the Am-241 is used as an alpha particle radioactive source to investigate the soft error mechanism in 65-nm and 90-nm static random accessmemory (SRAM). Combining reverse analysis, TRIM and CREME-MC Monte Carlo simulation, the energy transport process, deposited energy spectrum and cross-section characteristics of alpha particles in the device are revealed. The results show that the soft error sensitivity of the 65-nm device is much higher than that of the 90-nm device, and no flipping polarity is found. According to the real-time measured soft error rate at an altitude of 4300 m in Tibetan Yangbajing area, the thermal neutron sensitivity and alpha particle soft error rate, the overall soft error rate of 65-nm SRAM used at sea level of Beijing city is 429 FIT/Mb, and the contribution from alpha particles is 70.63%. Based on the results of reverse analysis, a three-dimensional simulation model of the device is constructed to study the influence of the incident angle of alpha particles on the single event upset characteristics. It is found that the corresponding deposition energy value at the peak of the number of particles in the sensitive region decreases by 40% with the incident angle increasing from 0° to 60°. While the single event upset cross sectionincreases by 79% due to the apparent single event upset edge effect in a sensitive region of the 65-nm device.

Test point load test requires relatively small load, its instrument is portable, it can be easily applied to on-site testing,which may pave the way for the development of the fieldstrength of rock mechanics test, widely promoted in engineering construction, has a large space for development. When selecting the uniform rock do the load and saturation points uniaxial compression test respectively, and comparing the analysis of the two trials correlation between the results obtained by the method, the results showed that: point load test as a qualitative and semi-quantitative indicators are needed to meet the requiement of project, but if we put it as a fully quantitative indicators ,which will lead to large errors,and even lead to sweeping errors.

In order to investigate the relation between uniaxial compressive strength and point load strength, several homogeneous rock specimens were tested, and the influence of the different rock type was investigated using regression analysis and the derived equations were statistically tested. The test result show that there are some correlations and trends between uniaxial compressive strength and point load strength, the shape size and lithology of rock specimens have important influence on the result of point load test, and the greain size, the mineral compositon and the structral compact are key factors. It is difficult to realize that using one or several function to describe all internal relations between uniaxial compressive strength and point load strength.

Analyzing and Evaluating the stability of the surrounding rock is an indispensable and important part in the tunnel design. In this paper, the surrounding rock stability of Danba hydropower station diversion tunnel is dealt with, FLAC3Dsoftware is used for stability analysis. Selecting three different cross sections for calculation models, comparing with the displacement and principal stress and the plastic zone which calculated by FLAC3D, we can evaluate their stability and get the best diversion tunnel design.

In view of the definition on the slope of the specification, the classification of water conservancy engineering slope is obtained. Through the analysis of the unique features of different types of slope of specific projects, the focus of different slope is pointed out. After the risk analysis and evaluation on the slope, according to the characteristics of the water conservancy engineering slope, it is proposed that engineering measures and non-engineering measures can be adopted to transfer or reduce the risk.

Concrete filled steel tubular (CFST) column-beam joint with the column tube discontinuous in joint zone is a new type of joint. Firstly, the results of the cyclic loading experiments on this joint were introduced briefly. Then numerical simulation of the experiment process was carried out by OPENSEES, and the load-displacement curves, strength degradation, stiffness degradation of the specimens were studied. The analysis results exhibit good agreement with the experimental ones. OPENSEES can simulate two types of failure, including joint failure and beam failure. Based on specimen S3, parametric analysis were conducted to research the strength degradation and stiffness degradation in models with different reinforcement ratios and reinforcement diameters. The results indicate that models with higher reinforcement ratio of the beams will result in joint failure under cyclic reverse loading, and their load-displacement curves are pinched and ultimate bearing capacity would not increase while strength degradation and stiffness degradation would appear obviously.

In order to research the relationship between the life of hull with different structure and the reliability while using, a life estimation method for hull based on test was proposed. By assuming that the hull life span satisfied the Weibull distribution, with zero-failure data, confidence limit γ and reliability R, the confidence lower limit of reliable life were given according to test data of the hull life span. If the lower limit of the shape parameters of the Weibull distribution were known, this method can accumulate all of zero-failure data to increase the analysis presion of reliability greatly. At last, using this method, under the hull reliability R and the confidence γ, the confidence lower limit of reliable life with the hull structures as steel, titanium alloy and aluminum alloy were computed. The results indicate that the method is easy to compute and very convenient for engineering application.

The ethylene diamine, acetone and dibutyl phthalate are used as the curing agent, diluent and flexibilizer in the researches about epoxy mortar. But in fact these materials are difficult to be bought in market because of the toxicity. The influence of the additives on the workability and mechanical properties of epoxy mortar are investigated by using the orthogonal experimental design method in this work, and all the additives can be bought easily from the market. The results are as followings:(1) the influence of curing agent on the initial setting time, the toughness and the 1d, 3d compressive strength of epoxy mortar is significant; (2) the influence of diluent on the workability of epoxy mortar is significant; (3) the influence of flexibilizer on the 7d compressive strength is significant; (4) the interface bonding of epoxy mortar and cement mortar is good; (5) the optimum proportion by mass for epoxy mortar is, epoxy resin: curing agent: diluent: fumed silica =1:0.5:0.1:0.05:0.01.

Sound comfort becomes more and more important in residential houses. Home appliance is one of the main sources of indoor noise. Noise emission is a distinctive feature for the selection of the home appliances. Noise levels in household appliances are increasingly attracting attention from manufacturers and customers. Refrigerators as common appliances used by most families run continuously all day. It produces a lot of noises. National standards have published severe rules on the acceptable noise levels, and noise-free operation becomes the preferred choice of customers in the refrigerators choosing. Therefore, it is necessary to reduce the noise level of refrigerator. In this paper, the noise control study has been carried on a type of air-cooled household refrigerator. The noise level of the refrigerator was tested under different operation conditions at first. Then the maximum sound pressure level and noise characters were obtained by analyse the spectra of the noises. Test data shown that the refrigerator noises are mainly composed of compressor and fan noises. According to the characteristics of the compressor and fan noise, a method of using sound insulation board was proposed to reduce the compressor noise. Considering the actual installation restrictions and the compressor cooling demand, a kind of sound insulation board with holes was applied. Experimental studies indicated that the proposed noise control method can suppress the noise of the household refrigerator effectively.

Genetic responses of the edible seaweed Porphyra yezoensis tissue to acid shock have been compared using differential display technique. The tissue was challenged in seawater containing hydrogen chloride (pH 3.0) for 5 min, then rehabilitated in normal seawater for 10 min, 30 min, 60 min and 4 hrs. Total RNA extracted by the LiCl-guanidium method was reverse transcribed and amplified by PCR with arbitrary primers. The amplified fragment responded by the acid shock was selectively isolated from agarose gel and sequenced with DNA auto sequencer. Sequence (1056 bp) of the cDNA contained at least two genes for ASP7K (MW 7418) and ASP5K (MW 5512) proteins.

Plant ash and soil drainage, derived by frequent mountain fires during winter, might cause biological contamination to seaweeds at seashore and river mouse area. To thalli of Ulva pertusa, maximum non-lethal concentration(MNLC), lethal concentration 50 and minimum lethal concentration (MLC) of pine needle ash were shown as 60, 350 and 550 mg/mL, respectively. The yellow loess and granite sand did not damage at concentrations of 20 and 200 mg/mL, respectively To thalli of Porphyra yezoensis, the MNLC, LC5O, MLC of pine needle ash were shown as 0.08, 0.4 and 1.0 mg/mL, respectively. Effects of yellow loess and granite sand were approximately 1/2 and 1/10 of the ash. To thalli of Undaria pinnatifida, the pine needle ash, yellow loess and granite sand did not damage at the concentration range of 20 to 40 mg/mL. Change of pigments was also determined at the MNLC, and MLC of pine needle ash. Among three seaweeds tested, P. yezoensis produced the most 2.7-fold of lutein and 2.3-fold of at of the ash. Thus the P. yezoensis, appeared as a sensitive indicator, could be used as one of test organisms for determination of the biological effect of pollutants contaminated in marine environment.

Nuclear 18S ribosomal RNA gene (185 rDNA) from the aquaculturable seaweed Porphya tenera (Bangiales, Rhodophyta) was amplified using the polymerase chain reaction and its sequence was analysed. Complete 185 rDNA has an 1,822 bp exon and a 510 bp intron. The G+C contents of exon and intron were respectively. The exon sequence showed homology to the GebBank accession number AB029880 of the Japanese P. tenera. The intron region that is inserted upstream between 568 and 1,079 showed homology to the AB029880.

Nuclear 18S ribosomal RNA gene (185 rDNA) from the aquaculturable seaweed Porphya yezoensis (Bangiales, Rhodophyta) was amplified using the polymerase chain reaction and its sequence was analysed. Complete 185 rDNA has an 1823 bp exon and a 514 bp intron. The G+ C contents of exon and intron were and , respectively. The exon sequence showed homology to the GenBank accession number AB013177 of the Japanese p. yezoensis. The intron region that was inserted upstream between 568 and 1083 showed homology to the AB013177.

Due to the phase modulation is more sensible to early local gear faults than the amplitude modulation. This paper proposed a new method using phase demodulation based on resonance band for early detection of gear tooth cracking fault. The proposed scheme based on the fact that gear tooth crack can excite impacts which will stimulate the structural/transducer resonances when the cracked tooth is engaged. In this scheme, the synchronous averaging methods are used to eliminate the regular signal first. Then, frequency shift method is used to pick out the phase modulation harmonics in resonant band. At last, the features of gear fault can be indicated by demodulation the phase modulation harmonics. Simulation studies indicated that this method is an effective tool for early detection of local gear faults.

Role of peroxynitrite in [3H] gamma-aminobutyric acid (GABA) release evoked by N-methyl-D-aspartate (NMDA) and S-nitroso-N-acetyl-penicillamine (SNAP) and mechanisms of [3H]GABA release induced by peroxynitrite in comparison with those induced by NMDA and SNAP were investigated using cerebrocortical neurons. NMDA dose dependently increased [3H]GABA release, which was significantly inhibited by hemoglobin and superoxide scavengers, Cu2+, Zn(2+)-superoxide dismutase and ceruloplasmin. The NMDA-evoked [3H]GABA release was significantly suppressed by GABA transport inhibitors and inhibitors of voltage-dependent L-typed Ca2+ channel. The SNAP-evoked [3H]GABA release was significantly reduced by Ca2+ withdrawal and by GABA transport inhibitors either in the presence or absence of Ca2+. Similar patterns of [3H]GABA release induced by peroxynitrite were observed. These results indicate that peroxynitrite formed by the reaction of NO with superoxide participates, in part, in the release of [3H]GABA induced by NMDA and SNAP.

Qiemo was an ancient country on the south branch of the Silk Road. The Zagunluke tomb site is located at the Qiemo County of the Xinjiang Uygur Autonomous Region. Glass beads and only colourless glass cup were excavated from the 3rd cultural layer of the tomb site M133 and M49, dated between the 1st AD-6th AD. LA-ICP-AES was applied to analyse chemical composition of these glass finds with the corning glass as reference. According to the result, characteristics of chemical composition are very similar to typical soda-lime glass, which indicates the glasses were imported productions from the west. These soda-lime glasses were divided into two groups in terms of flux source: natron glass and plant ash glass. This analytical research indicates the history of glass trade and communication between the East and the West on the Silk Road.

To study whether the porcine alpha1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte negatively expresses GT mRNA and resists to the cytotoxicity of nature antibody in human serum.The porcine alpha1, 3 galactosyltransferase gene siRNA targeted vector (pPNTloxPGTsiRNA) were construct with pPNTloxPGT and pMXSV/U6 vector. Positive-negative selection was used to produce a heterozygous pPNTloxPGTsiRNA knockout (+/-) clone. The GT mRNA expressions were detected with northern blot. Complement-mediated NAb cytotoxicity after incubation of hepatocytes with NAbs and complement was determined using 3- (4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium(MTS, tetrazolium salt) colorimetric assay.The pPNTloxPGTsiRNA targeted porcine hepatocyte (+/-) negative express GT mRNA. Only 14% to 18% cytotoxicity can be detected at the highest serum concentration. The pPNTloxPGT targeted porcine hepatocyte (+/-) express GT mRNA just as the wild type porcine cells and the cytotoxicity are 77% to 83%.The porcine a1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte (+/-) negative express GT and resisted to nature antibody in human serum.

The capillary model was used to analyze the hydraulic conditions in the deep bed filtration process. The physicochemical interaction forces between the filter media and suspended particles and their influence on deep bed filtration process were also studied theoretically. Through the comparison of the hydraulic and physicochemical forces, the key influencing factors on the filtration process were proposed and investigated. Pilot study of the microflocculation deep bed filtration was carried out in the No. 9 Potable Water Treatment Plant of Beijing, and the experimental results of hydraulic head loss, particle distribution and entrapment were presented. The theoretical prediction was reasonably consistent with the experimental results under different conditions, which indicated that the regulation and control of micro-flocculation and deep bed filtration could be realized by the evaluation of the physicochemical interactions. Further theoretical and experimental research should be carried out to investigate the interaction mechanism and its application in the deep bed filtration and other cases.

The effect of hydroxyl radical scavengers on acetylcholine (ACh) release evoked by nitric oxide (NO) generators and N-methyl-D-aspartate (NMDA) was investigated. Dimethylthiourea enhanced dose-dependently NO generators-evoked ACh release. Similarly, uric acid and mannitol significantly facilitated ACh release evoked by NO generators. The NMDA-induced ACh release was also significantly facilitated by hydroxyl radical scavengers. These scavengers themselves showed no effects on ACh release. These results suggest that hydroxyl radicals may modify the mechanism for NO-evoked ACh release.

Functional roles of peroxynitrite in N-methyl- d -aspartate (NMDA)- and sodium nitroprusside (SNP)-evoked releases of acetylcholine (ACh) from cerebral cortical neurons in primary culture have been investigated. NMDA increased the release of ACh in a dose-dependent manner, which was significantly suppressed by (+)-5-methyl-10,11-dihydro-5H-dibenzo-[a,d]cycloheptan-5,10-imine (MK-801), a non-competitive antagonist specific for the NMDA receptor complex, and NO synthase inhibitors. SNP also showed a concentration-dependent increase in ACh release. Hemoglobin significantly abolished the stimulatory effects of both NMDA and SNP on ACh release. In addition, superoxide anion scavengers such as superoxide dismutase and ceruloplasmin significantly reduced the increased ACh release evoked by NMDA and SNP. Synthesized peroxynitrite dose-dependently elevated the release of ACh. These results indicate that the increased release of ACh by NMDA and SNP is mediated through peroxynitrite formed in the reaction of superoxide anion with nitric oxide produced by NMDA receptor activation and liberated from SNP rather than nitric oxide itself.