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We studied the effects of 7-crop rotations and continuous - monocropping systems on soil microorganism and its feedback. The results showed that absolute abundance of soil bacteria (Pseudomonas and Bacillus) in tomato - celery - cucumber - cabbage and cucumber - tomato - cucumber - cabbage rotation were significantly higher than control (CK). Absolute abundance of soil fungi in tomato - celery - cucumber - cabbage, kidney bean - celery - cucumber - cabbage, cucumber - kidney bean - cucumber - cabbage and cucumber - tomato - cucumber - cabbage rotation were significantly higher than CK. Dry weight of cucumber seedlings was significantly positively correlated with bacterial (Pseudomonas and Bacillus) abundance, and negatively correlated with fungal count. The results of inoculation with Fusarium oxysporum f.sp. cucumerinum showed that plant dry weight of cucumber seedlings in tomato - celery - cucumber - cabbage, cucumber - kidney bean - cucumber - cabbage, cucumber - tomato - cucumber - cabbage rotation soil was significantly higher than other treatments, and their disease index was significantly lower than other treatments. There was no significant difference in dry weight of cucumber seedlings in rotation and CK in the soil sterilization test. The results of plant - soil feedback experiment showed that soil microbial changes caused by different rotation patterns had a positive feedback effect on growth of cucumber seedlings.

The multiple factors related moisture absorption model was established through the moisture absorption test of GFRP bars embedded in steam-curing concrete, which considered different curing temperatures, different thicknesses of protective layer and different diameters of GFRP bars as analysis variables. Semi-reliability probability damage assessment of GFRP bars embedded in steam-curing concrete was described by introduced the reliability and stochastic theory. Subsequently, the tensile test of GFRP bars was carried out to verify the feasibility of the damage assessment. The results showed that the moisture absorption curves of GFRP bars were basically in line with the Fick’s law. In addition, the influences of the curing temperature, the thickness of protective layer and the diameter on moisture absorption performance were presented. The Semi-reliability probability damage assessment model of GFRP bars embedded in steam-curing concrete beams adequately considered the multiple factors related moisture absorption as well as the uncertainty and randomness of the influencing factors during the process of moisture absorption.

This study investigated the effects of a traditional Chinese medicine formula (TCMF) on growth performance, and meat quality and fatty acid profiles of finishing pigs. Ninety 146-day-old Pietrain × Duroc × Landrace × Yorkshire pigs (84.1 ± 0.86 kg BW) were assigned randomly to three treatments with five replicates, six pigs per pen. Control group was fed basal diet and the other two groups were fed basal diet plus different doses of the TCMF (TCMF1: 2.5 g/kg feed; TCMF2: 5 g/kg feed). Growth performance was unaffected by TCMF ( P > 0.05). Pigs fed the TCMF had higher crude fat content in muscle ( P P P P > 0.05). The concentration of vaccenic acid in longissimus dorsi and of total unsaturated fatty acids in abdominal adipose tissue were increased by TCMF1 ( P P

6Li solid-state nuclear magnetic resonance (ssNMR) is used here to evaluate a series of Li2Mn1–yFeyP2O7 cathode materials in an effort to quantify ion exchange rates and diffusion pathways. Magic angle spinning (MAS) NMR of the series of mixed metal pyrophosphates reveals a trade-off between electrochemical performance and well-resolved NMR spectra resulting from the change in electronic structure of the transition metal redox center. In addition, 1D 6Li selective inversion NMR is employed to characterize Li ion dynamics in the fully Mn substituted member of the pyrophosphate series, where three of the four unique Li resonances are well resolved and labeled AB, C, and D, with AB corresponding to Li ions within one tunnel, and C and D Li ions residing in another. Despite limited inversion efficiency it is found that the utility of this experiment is not compromised so long as the initial magnetization conditions are well-defined. Initial fitting procedures involved the inclusion of all possible exchange pa...

To optimize the process parameters of cold rolling the finite element model of metal plastic flow in cold rolling was carried out based on the cold forming principle of ballscrew and rigid-plastic finite element theory. The adaptive mesh refinement was utilized to improve calculation accuracy in large plastic deformation zone. Using lagrangian algorithm the processing of cold rolling is numerically simulated by DEFORM-3D. The appropriate revolution speed is got by analyzing different simulation results such as the maximum stress and maximum strain and flow velocity etc. under different revolution speeds. The appropriate transmission ratio is got by analyzing different simulation results such as the maximum stress and maximum strain and flow velocity etc. under different transmission ratios. The research results provide evidence for process parameters optimization. At the same time those research results lay a foundation of further study of forming mechanism.

Cold rolling is an advanced splinterless processing method, which has been applied to process many parts, like spur gears, helical gears, spline shaft and ballscrew, etc. Ballscrew which determines the motion characteristics has been used as key transmission part of ballscrew pair. According to differential geometry and meshing theory, the mathematic model of ballscrew manufactured by cold rolling is built, and the normal section equation of ballscrew is derivated in this paper. The cold forming principle of ballscrew is investigated; the meshing model, the contact line and theoretical errors of the ballscrew are constructed. The objective moving laws between roller and workpiece are revealed by analyzing the meshing model and the contact line, the processing method of cold-rolling is considered as the generating method which can lay the foundation for roller design by analyzing forming principle. By analyzing the profile error and the error of the actual helix of the centrode of ball, the error generation causes are discovered, and the calculation methods of the profile error and the spiral error of ballscrew are proposed. By analyzing the error evolution and taking a certain type of ballscrew for example, the results indicate that the profile error is brought by roller designing, and the spiral error is caused by discontinuous contact.

Sensory hair-cell development, function, and regeneration are fundamental processes that are challenging to study in mammalian systems. Zebrafish are an excellent alternative model to study hair cells because they have an external auxiliary organ called the lateral line. The hair cells of the lateral line are easily accessible, which makes them suitable for live, function-based fluorescence imaging. In this chapter, we describe methods to perform functional calcium imaging in zebrafish lateral-line hair cells. We compare genetically encoded calcium indicators that have been used previously to measure calcium in lateral-line hair cells. We also outline equipment required for calcium imaging and compare different imaging systems. Lastly, we discuss how to set up optimal imaging parameters and how to process and visualize calcium signals. Overall, using these methods, in vivo calcium imaging is a powerful tool to examine sensory hair-cell function in an intact organism.

In this paper, we have developed an electrothermally driven RF MEMS capacitive switch, where the HfO2 film, deposited by atomic layer deposition (ALD) process, was used as insulation dielectric between signal line and ground line. Thanks to high permittivity and excellent electrical and thermal isolation properties of the HfO2 film, as well as high driving force of the electrothermal actuator, the isolation of the proposed switch coated with the HfO2 film was up to 60 dB at 35 GHz and the bandwidth of isolation better than 25 dB was 10.5 GHz. The results demonstrate that the HfO2 film is a good candidate material serving as sidewall dielectric to realize the lateral capacitive switch with high RF performances.

The effectiveness of two different selective inversion methods is investigated to determine timescales of Li ion mobility in paramagnetic Li intercalation materials. The first method is 1D exchange spectroscopy, which employs a 90°-τ(1)-90° sequence for selective inversion of a Li resonance undergoing site exchange. The experiment is most easily applied when the first delay period, τ(1), is set to the frequency difference between two resonances undergoing ion exchange. This enables the determination of ion hopping timescales for single exchange pair systems only. To measure ion dynamics in systems having more than one exchange process, a second selective inversion method was tested on two paramagnetic Li intercalation materials. This second technique, replaces the 90°-τ(1)-90° portion of 1D EXSY with a long, selective shaped pulse (SP). Two paramagnetic solid-state materials, which are both cathode materials for lithion ion batteries, were chosen as model compounds to test the effectiveness of both the selective inversion methods. The first compound, Li(2)VPO(4)F, was chosen as it hosts two Li sites with 1-exchange process. The second model compound is a 3-site, 3-exchange process system, Li(2)VOPO(4). For the 2-site material, Li(2)VPO(4)F, the timescales of the single A-B exchange process were found to be within error of one another regardless of the inversion method. For the 3 Li-site material Li(2)VOPO(4), the three exchange processes, AB, BC, and AC, were found to be on the millisecond timescale as revealed using the SP method. These timescales were determined over a variable temperature range where activation energies extended from 0.6 ± 0.1 eV up to 0.9 ± 0.2 eV.

The crystal structures, band structures, elastic constants, hardness, and optical properties of pyrite-type dinitrides (CN 2 , SiN 2 , and GeN 2 ) are obtained from the density functional theory using the plane-wave pseudopotential (PWP) method within the local density and generalized gradient approximations. The formation enthalpies for AN 2 (A=C, Si, and Ge) compounds suggest the three structures that are stable. The calculated band structures show the indirect gaps ( Γ − R ) in CN 2 , SiN 2 , and GeN 2 . The intrinsic hardnesses of AN 2 (A=C, Si, and Ge ) compounds are calculated. Our results show that the cubic CN 2 and SiN 2 are superhard materials. Furthermore, we studied the optical properties such as the complex dielectric function and the electron energy loss spectra.

To optimize the process parameters of cold rolling the finite element model of metal plastic flow in cold rolling was carried out based on the cold forming principle of ballscrew and rigid-plastic finite element theory. The adaptive mesh refinement was utilized to improve calculation accuracy in large plastic deformation zone. Using lagrangian algorithm the processing of cold rolling is numerically simulated by DEFORM-3D. The appropriate revolution speed is got by analyzing different simulation results such as the maximum stress and maximum strain and flow velocity etc. under different revolution speeds. The appropriate transmission ratio is got by analyzing different simulation results such as the maximum stress and maximum strain and flow velocity etc. under different transmission ratios. The research results provide evidence for process parameters optimization. At the same time those research results lay a foundation of further study of forming mechanism.

According to the kinematics theory of part surface forming motion and engagement principle, shaping movement of ballscrew manufactured by cold rolling has been investigated. The motion relationship and mathematical model of ballscrew have been built. By means of ADAMS and MATLAB the motion simulation and numerical calculation of cold rolling have been done. From analysis results, motion relationships between roller and workpiece and forming principle of cold rolling have been revealed. These studies will provide quantitative basis for technologic research of cold rolling and promote the study of ballscrew’s cold rolling forming mechanism.

The energetics, electronic structure, and optical properties of Al-doped γ-Si 3 N 4 with different concentration are studied based on density function theory within the generalized gradient approximation (GGA). The binding energy and the formation energy suggest that Al impurities prefer to substitute Si at octahedral sites. Different doping concentrations are considered and the corresponding density of states (DOS) analyzed. Calculated DOS indicates that there are holes in the top of the valance band after doping, meaning a p-type doping. We study the complex dielectric function, the absorption coefficient, and the electron energy loss spectra. It is demonstrated that for the low Al concentration, the material exhibits the dielectric behavior and for the high Al concentration, the material is possible to exhibit the metallic behavior. The γ-Si 3 N 4 doped with Al has a much higher static dielectric constant than undoped γ-Si 3 N 4, implying its potential applications in electronics and optics.

Hydrous ruthenium oxide/activated carbon black (RuOx/ACB) composite was synthesized for the first time for supercapacitors by a chemical impregnation method. The RuOx/ACB composite is characterized by thermogravimetric analysis (TGA), field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). The results of TGA and TEM characterization showed that the reaction temperature of composite moved to lower temperature due to the catalytic effect of RuOx. XRD characterization of RuOx/AC illustrated that amorphous hydrous RuOx structure maintained in the composite heated at 150 °C. The equivalent series resistance (ESR) of the composite almost increased with the increase of RuOx content in the composite. The specific capacitance (Csp) of the composite increased with increasing RuOx content in the composite while the Csp of RuOx decreased from 1255.8 to 533.7 F g−1. The above results showed that the utilization of RuOx decreased with higher loading RuOx on ACB.

This study focused on the evaluation of performance and mechanisms of a high-rate algal pond system (HRAP System) in nitrogen and phosphorus removal for rural domestic sewage treatment. A pilot scale HRAP System was located at Yangzhu Village, Jiangsu Province, east China, with treatment processes including a septic tank, two stages of HRAPs and an aquatic pond. Results showed that the HRAP System had a good performance in nutrient removal, especially in NH + 4 ‐N removal. Total removal efficiencies of COD, TN, NH + 4 ‐N and TP were 80, 51.8, 90.2 and 52.1%, respectively. About 61.6% of NH + 4 ‐N in the 1st-stage HRAP and 70.9% in the 2nd-stage HRAP were transformed into NO − 3 ‐N and NO 2 − ‐N through nitrification, and the nitrogen losses via ammonia volatilization was only 2.7% (for 1st-stage HRAP) and 8.8% (for 2nd-stage HRAP). The other 35.7% and 20.3% of NH + 4 ‐N removal were achieved by algae assimilation respectively. About 98.0% (for 1st-stage HRAP) and 84.8% (for 2nd-stage HRAP) removal of TN were attributed to algae sedimentation, while those through ammonia volatilization were only 2.0% (for 1st-stage HRAP) and 15.4% (for 2nd-stage HRAP), respectively. Therefore, the main mechanisms of NH + 4 ‐N removal in HRAP were nitrification and algae assimilation, and TN was mainly removed by algae sedimentation. About 50.7% (for 1st-stage HRAP) and 53.1% (for 2nd-stage HRAP) of phosphorus in the deposit were organic phosphates respectively, only 20.7% and 27.7% were calcium-bound and magnesium-bound phosphates. The removal mechanism of TP in HRAP could be mainly attributed to algae assimilation in forms of organic phosphate, and chemical precipitation in forms of calcium-bound and magnesium-bound.

We previously demonstrated that inactivation of Rho-kinase by hydroxyfasudil could impact N-methyl-d-aspartate (NMDA) excitatory interneurons in the hippocampus and attenuate the spatial learning and memory dysfunction of rats caused by chronic forebrain hypoperfusion ischemia. Complementary interactions between the excitatory neurotransmitter glutamate and the inhibitory neurotransmitter GABA form the molecular basis of synaptic plasticity and cognitive performance. However, whether the GABAergic inhibitory interneurons are involved in the mechanisms underlying these processes remains unclear. Here, we further examined the role of GABAergic interneurons in the neuroprotective effect of the Rho-kinase inhibitor. Chronic forebrain ischemia was induced in Wistar rats by bilateral common carotid artery occlusion (BCAO). The general synaptic transmission and long-term potentiation (LTP) of hippocampal CA3 neurons were evaluated at 30 days after sham surgery or BCAO. Real-time PCR and Western blot analyses were conducted to determine the effect of the Rho-kinase inhibitor hydroxyfasudil on GABAergic inhibitory interneuron expression and function after ischemia. Hydroxyfasudil showed no significant effect on general synaptic transmission, but it could abolish the inhibition of LTP induced by chronic forebrain ischemia. Moreover, the mRNA and protein levels of GABAA and GABAB in three brain regions after ischemia were markedly decreased, and hydroxyfasudil could up-regulate all mRNA and protein expression levels in these areas except for GABAA mRNA in the cerebral cortex and striatum. Using phosphorylation antibodies against specific sites on the GABAA and GABAB receptors, we further demonstrated that hydroxyfasudil could inhibit GABAergic interneuron phosphorylation triggered by the theta burst stimulation. In summary, our results indicated that the inactivation of Rho-kinase could enhance GABAA and GABAB expressions by different mechanisms to guarantee the induction of hippocampal LTP, and it could decrease the phosphorylation level of GABAergic inhibitory interneurons to promote the LTP induction rate and magnitude, hence improving the cognitive deficit suffered after chronic forebrain ischemia.

The reactivities of Australian coals and one American coal with methane or methane-hydrogen mixtures, in the range 350–400°C and a range of pressures (6.0–8.3 MPa, cold) have been examined. The effects of aluminophosphates (AlPO) or zeolite catalysts, with and without exchanged metals, on reactivity have also been examined. Yields of dichloromethane extractable material are increased by using a methane rather than a nitrogen atmosphere and different catalysts assist dissolution to various extents. It appears that surface exchanged catalysts are effective, but incorporating metals during AlPO lattice formation is detrimental. Aluminium phosphate catalysts are unstable to water produced during coal conversion, but are still able to increase extraction yields. For the American coal, under methane-hydrogen and a copper exchanged zeolite, 51.5% conversion was obtained, with a product selectivity close to that obtained under hydrogen alone, and with only 2% hydrogen consumption. The conversion under methane-hydrogen was close to that obtained under hydrogen alone, while a linear dependence of conversion on proportion of methane would predict a 43% conversion under methane-hydrogen. This illustrates a synergistic effect of the methane-hydrogen atmosphere for coal liquefaction using this catalyst system.

In this paper, we developed an electrothermally driven RF MEMS capacitive switch, where the HfO 2 film, deposited by atomic layer deposition (ALD) process, was used as insulation dielectric of the capacitor formed by the signal line and switching plate. Thanks high permittivity and excellent electrical and thermal isolation properties of the HfO 2 film, as well as high driving force of the electrothermal actuator, the single side isolation of the proposed switch with HfO 2 film was up to 17dB at 20GHz. The results demonstrate that the HfO 2 film is a good candidate material acting as sidewall dielectric to realize the lateral capacitive switch.

“Fault Tree Analysis” uses the logical model and mapping methods to analyse, calculate or estimate the probability of phylogenetic. Thus, the reliability of the system, safety and risk could be assessed. They have been widely used in system's reliability study and to quantify the correlation of potential risk of the system. In the existing of reliability analysis, the time factor generally doesn't need to be taken into account. However, composition properties of the materials decrease would lead to the reduction of the level of structural reliability. Therefore, structure's reliability is actually an amount of time-varying. Comprehensive consideration of the above factors, the analysis of a variety of factors will impact on the service life of pre-stressed concrete girder bridge, to build bridge structure analysis model. From the calculation of time-varying structure system's reliability, the service life of bridge could be evaluated to find safety and reliability of structure.

This paper studies the early trends of enterprise resource planning (ERP) in China via an executive survey and subsequent statistical analysis. While ERP has been contributed to increased efficiency, increased revenue, and reduced costs, companies with horror stories about their ERP implementation are not uncommon. ERP implementation in China is so new that, except for a few large enterprises, the vast majority of Chinese enterprises are still on the sidelines weighing pros and cons. Whereas it is complex at any company, ERP implementation will be especially challenging for Chinese enterprises due to small company sizes, transitional enterprise ownership from planned to market economy, and cultural and language barriers. Thus, this research scrutinizes such ERP pre-implementation concerns as key factors affecting ERP decisions, potential benefits, major obstacles to implementation, and unsettled issues with managerial implications to Chinese enterprises and ERP vendors.

Mossbauer spectroscopy has been used as a quantitative analytical method for determining variations in the retained austenite concentration in FeMnC dual-phase steels after mechanical deformation and thermal treatment. It is shown that retained austenite is transformed to martensite during the deformation, its concentration being reduced from 7 wt.% to less than 1 wt.% for a deformation of 20%. This transformation is also observed, but to a lesser extent, after the samples had been cooled in liquid nitrogen.