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With the increasing utilization of electronic equipment in the power system, sub-synchronous oscillation (SSO) has occurred many times and caused off-grid accidents because of power oscillation. SSO has become one of the main problems that restrict the development of new energy. In this paper, power oscillation in grid-side converters (GSCs) in doubly-fed induction generators (DFIGs) under SSO is studied. Firstly, the influence mechanism of SSO on GSC multipath disturbance is studied. Secondly, the problem of coupling oscillation caused by PLL output errors after coordinate transformation is studied, and the mathematical model of GSC output power considering SSO multipath disturbance is established. By analyzing the oscillation suppression ability of the quasi-resonant controller under variable SSO states, the key influencing factors of SSO for GSC power oscillation suppression strategies are determined. Furthermore, based on the above theoretical analysis and research, an improved PLL is designed to eliminate the influence of its output errors on the disturbance of GSC. At the same time, a DFIG-GSC power oscillation suppression strategy using an adaptive quasi-resonant controller is designed to eliminate the influence of SSO on the multi-path disturbance of GSC. Finally, the effectiveness of the proposed suppression strategy is verified using simulation and experimental results.

The solvent-free fast-curing coating for repairing is prepared using polyurea as matrix and graphite nanoplatelets (GNPs) as fillers. The effects of GNPs on the coating are studied. The coating is prepared by HDI tripolymer and polyetheramine. The GNPs is functionalized (f-GNPs) by aminopro-pyltriethoxysilane (APTES) in mixture of water and ethanol. The performances of the coatings are tested by salt spray time, polarization curves and electrochemical impedance. The coating presents solvent-free and fast-curing characteristics and is suitable for repairing. The f-GNPs provide both physical barrier and coulomb block for the coating. When the f-GNPs added amount is 0.6 wt%, the salt spray resistance time of the coating is more than 420 h, and the corrosion potential is –0.6428 V. The effects of GNPs on coating are investigated. The results can provide a new idea for preparation of anticorrosive coating used for repairing, and can benefit in-depth understanding of the influence of f-GNPs on the coatings. The coating for repairing is prepared by adding f-GNP as fillers. The anticorrosive mechanism and performance of the coating are discussed in detail.

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In this paper, we numerically demonstrated a dynamically tunable implementation of electromagnetically induced transparency (EIT) based on bright and dark modes coupling graphene-nanostrips. Two graphene-nanostrips are connected respectively with two metallic pads, which make Fermi energies of proposed two graphene-nanostrips can be independently tuned by changing bias voltage between the metallic pads and substrate, and the EIT window can be easily controlled than metallic and separated graphene structures. As a result, the EIT window has a significant tunable capacity, and the most remarkable characteristic of proposed structure is to achieve distinct transparency windows respectively at two perpendicular directions of polarization, which is not obtained or analyzed in the previous similar structures, and these merits exhibit the potential applications in sensor device.

In this paper, we numerically demonstrated a dynamically tunable implementation of electromagnetically induced transparency (EIT) response with two coupling graphene-nanostrips in terahertz region. Compared to the metal-based structures or separated graphene structures, the Fermi energies of proposed two coupling graphene-nanostrips can be independently tuned by changing bias voltage between the metallic pads and substrate, the EIT window which appears from the near-field coupling between two resonators can be dynamically tuned without reoptimizing and refabricating the structures. As a result, the EIT window has a significant tunable capacity which can realize a higher frequency modulation depth and control the amplitude of transmission peak at a fixed frequency; moreover, the group delay of transmission peak at a fixed frequency with the amplitude of over 0.95 could be dynamically tuned. These results would exhibit potential applications in modulators and tunable slow light devices.

Click-through rate (CTR) prediction is an essential task in industrial applications such as video recommendation. Recently, deep learning models have been proposed to learn the representation of users' overall interests, while ignoring the fact that interests may dynamically change over time. We argue that it is necessary to consider the continuous-time information in CTR models to track user interest trend from rich historical behaviors. In this paper, we propose a novel Deep Time-Stream framework (DTS) which introduces the time information by an ordinary differential equations (ODE). DTS continuously models the evolution of interests using a neural network, and thus is able to tackle the challenge of dynamically representing users' interests based on their historical behaviors. In addition, our framework can be seamlessly applied to any existing deep CTR models by leveraging the additional Time-Stream Module, while no changes are made to the original CTR models. Experiments on public dataset as well as real industry dataset with billions of samples demonstrate the effectiveness of proposed approaches, which achieve superior performance compared with existing methods., Comment: 8 pages. arXiv admin note: text overlap with arXiv:1809.03672 by other authors

Novel, one-dimensional Bi2O3–Bi14MoO24 heterostructures with high interface quality were synthesized by high temperature calcination of Bi2MoO6–Bi(OHC2O4)·2H2O precursors in air at 400 °C for 2 h. Bi14MoO24 grew on the Bi2O3 porous rods by crystallographic-oriented epitaxial growth, which increased the interface quality and then provided the smallest penetration barrier for electron–hole pair transfer between Bi2O3–Bi14MoO24 interfaces. The photocatalytic activity of the as-prepared products was evaluated by the degradation of methyl orange (MO) and phenol under solar/visible light irradiation. The results show that Bi2O3–Bi14MoO24 heterostructures display higher photocatalytic activity than that of the pure phase Bi2O3 and Bi14MoO24, and 100% phenol (10 mg L−1) can be degraded in 80 min under visible light irradiation using the Bi2O3–Bi14MoO24 (DS-2) heterostructure as photocatalyst. This enhanced photocatalytic performance is ascribed to the synergistic effect of the suitable band alignment of the Bi2O3 and Bi14MoO24, high interface quality and one-dimensionally ordered nanostructure. Radical scavenger experiments proved that the photogenerated holes and ˙O2− play key roles during the photodegradation process. This work offers an effective route to the design and fabrication of the junction structures with high interface quality for photocatalytic applications.

One-dimensional (1D) Bi12O17Br2/Bi24O31Br10 type II heterostructures were synthesized by calcining BiOBr/Bi(OHC2O4)·2H2O heterostructures in air at 400 °C. The photocatalytic activity of the as-prepared products was evaluated by the degradation of phenol and Rhodamin B (RhB) under visible light irradiation. The Bi12O17Br2/Bi24O31Br10 hierarchical heterostructures show enhanced visible light catalytic activity with the increase of the loaded/Bi24O31Br10 content, which results from the efficient separation of photogenerated charge carriers due to the staggered band potentials of the two materials. Radical scavenger experiments confirm that photogenerated holes (h+) are the main active species for oxidizing RhB molecules during the photocatalytic processes.

According to the the characteristic of tower structure and manufacturing property, the tower components are divided into the purchased (CP), the cooperative (CS), the inherit (CL), the key (CK) and so on. In order to ensure the product data integrity, consistency and correctness in chemical tower, different processing rules are adopted to CP, CS, CL, CKin mapping from EBOM(Engineering BOM) to PBOM(Proeess planning BOM). Based on EBOM view in UG, the mapping function from EBOM to PBOM is established to process all BOM data. PBOM view is created accordingly, to achieve computer aided design on BOM in the data management for chemical tower.

In UG(Unigraphics) environment, computer aided design on Bill of Materials (BOM) for chemical towel is developed using the development tools of VB. By depth traverse to the assembly structure tree,part properties are extracted from the parts information library in the tower assembly. These information are saved to the BOM management library, to generate the Engineering BOM(EBOM) view. The application module is the base for the further process planning and manufacturing.

In high voltage direct current (HVDC) cable accessories, there is a large difference of conductivity between crosses linked polyethylene (XLPE) and liquid silicone rubber (LSR), especially considering the presence of temperature gradient and the changing of operating temperature. In this paper, nano silicon carbide (SiC) was adopted to prepare five kinds of nanocomposites with filler fractions of 1%, 2%, 3%, 4% and 5%, respectively. The conductivity and DC breakdown strength of SiC/LSR nanocomposites were measured under different temperatures. The results show that the nano SiC doping does not has the great influence on LSR DC breakdown strength, and the nano SiC doping can improve the conductivity of LSR effectively, which can realize the conductivity matching between the LSR and XLPE to homogenize the electric field distribution in cable accessory.

In order to solve the problem of non-uniform electric field distribution in converter transformer barrier system caused by conductivity difference between the transformer oil and pressboard, the SiC(silicon carbide) modified pressboard was developed by nano doping method. The conductivity of modified pressboard was measured. The measuring results show that the conductivity of modified pressboard increases exponentially with the increase of nano SiC doping ratio. The electric field strength has obvious influence on conductivity at high nano doping ratio, which shows great nonlinear characteristic. Based on the nonlinear conductivity characteristic of modified pressboard, the homogenizing effect of the nano modified pressboard on electric field distribution was verified by simulation. The simulation results show that the electric field distribution under DC and polarity reversal voltage in barrier system can be well homogenized by using the nonlinear characteristic of nano modified pressboard.

The cadmium removed from sediment by rhamnolipid biosurfactant was explored in laboratory scale. The results suggest that the biosurfactant can remove cadmium from the sediment efficiently, 40% more than SDS. 200 mg/L rhamnolipid biosurfactant can get 84.02% cadmium removal efficiency from the sediment which contained 0.42 mg/g cadmium. pH affect cadmium removal by rhamnolipid, the best pH was 10. Leaching could also affect cadmium removal, there was a remarkable increasing of cadmium removal efficiency after the second washing, and after 48 h leaching cadmium removal and cadmium absorption got the balance.

Artificial organic polymer flocculants has been widely applied in water treatment; however, disadvantages of nonbiodegradable and poisonous may cause another environmental problem. This paper established an effective water treatment technique using Abelmoschusmoschatu (Okra) in combining of glue extraction process and flocculating process, with fully consideration of factors such as treating time, cost, and efficiency. Results showed that ethanol extraction was an effective method for extraction of glue form Okra. After being soaked in distilled water overnight with ratios of material to solvent, and was extracted by ethanol with volume percentage of 50% at stable temperature of 70 °C for one hour, the extraction rate of Okra glue could be as high as 18.38%. The glue usage of 0.015-0.020 g.L-1 and flocculating time of five minutes could be the optimal usage in treating suspending liquid of kaolin, with the turbidity of 3.0 g.L-1. The processes are low cost, simple, efficient, and low pollution, having broad application prospects.

In this paper, a novel EIT analogue consisting of metal-based resonator integrated with graphene is proposed, which can achieve tunable EIT-like effects in terahertz frequencies. For practical applications, a thin Si layer is grown on the resonator to provide a flat surface to transfer monolayer graphene using a wet transfer method. Numerical and theoretical investigations on the tunable EIT-like effect are carried out. The simulations reveal that EIT-like phenomenon is induced by coupling of bright-dark mode of metal-based resonator. Further investigations reveal that the amplitude of EIT window could be modulated by changing the Fermi level of graphene meanwhile the resonant frequencies exhibits slight shift. The physical mechanism underling the modulation phenomenon is mainly attributed to the damping rate of the dark mode and bright mode resonators, which is verified by theoretical analysis of classical two-particle model and absorption of proposed EIT-like analogue. The retrieved effective permittivity and permeability of the proposed metamaterial cell clearly exhibit dispersion in dependence of Fermi level of graphene. This work will offer a new perspective application in terahertz modulation and slow light devices.

A novel one-dimensional (1D) Bi2O3 nanorod–Bi2WO6 nanosheet p–n junction photocatalyst was prepared by a three-step synthetic route. The obtained products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and N2-sorption–desorption and Brunauer–Emmett–Teller (BET) surface area. Bi2O3 rods with the diameter of about 200 nm were obtained by calcining a Bi(OHC2O4)·2H2O precursor. Bi2WO6 nanosheets vertically grew on the Bi2O3 rods along the long axial direction. The photocatalytic activity required to degrade Rhodamine B (RhB) and phenol under solar/visible light by p–n junction of Bi2O3–Bi2WO6 nanorods was investigated. The results demonstrate that the novel Bi2O3–Bi2WO6 p–n heterostructures display higher photocatalytic activity than single Bi2O3 nanorods or Bi2WO6 flowers. The enhancement of the photocatalytic activity of the Bi2O3–Bi2WO6 p–n junction structures can be ascribed to strong visible light absorption and the effective separation of photogenerated electrons and holes by the internal electrostatic field in the junction region. More importantly, 1D p–n heterostructures made of ordered nanosheets are beneficial for the transport of photogenerated carriers and for increasing the rate of the photocatalytic reaction. This work could offer a new insight into the design and fabrication of advanced materials with heterojunction structures for photocatalytic applications and optoelectronic devices.

Band-gap narrowing is of significance and an advantage for potential visible-light photocatalytic applications. Here we report an effective strategy for the large-scale synthesis of yellow ZnO mesocrystals with a narrow band-gap (Eg = 3.09 eV) and visible-light response using the Zn(OH)F precursor. Raman and X-ray photoelectron spectroscopy (XPS) spectra reveal that a large amount of oxygen vacancies exist in the yellow ZnO mesocrystals, and that the concentration of oxygen defects decreases with an increase of the annealing temperature in air. Oxygen vacancies result in a narrowing of the band-gap and an increase the visible-light response of the yellow ZnO. Electron paramagnetic resonance (EPR) spectra confirm that abundant surface defects exist in yellow ZnO, leading to strong photoluminescence emission. The yellow ZnO mesocrystals are found to be efficient for the photodecomposition of methyl blue (MB) under visible-light irradiation. It is demonstrated that highly ordered porous mesocrystals are favorable for directional transport and highly efficient separation of charge carriers. Notably, our yellow ZnO microring sample is very stable for at least one year. Therefore, our present work highlights the feasibility of the simultaneous engineering of oxygen vacancies and visible-light response for the design of novel ZnO-based materials for solar energy conversion.

The vibrating roller crusher make relative vibration generated by two rigid bodies to bring high-frequency impulse. The force impact on grain layer (or granular) in chamber, which makes grain crush. Based on the newton's law, the vibration differential equations and dynamics model in vibration-impact crushing system of a unilateral single-mass are established. By dynamic analysis, amplitude frequency curve, hysteresis impact curve and energy absorption curve are all found. On the numerical values, principal resonance of system on forced oscillation is solved. Displacement, velocity and acceleration with the time history are induced. The results showed that the movement of a mass is not simple harmonic motion. From clearance and vibration frequency, influence laws on amplitude frequency, impact, energy absorption is also established.

The present paper studies the biodegradability of partially hydrolyzed polyacrylamide (HPAM) resulting from the waste water of an oil field after carrying out chemically based oil recovery methods. Three aerobic bacteria strains, PM-1, PM-2, PM-3 and PM-4 were isolated from the wastewater. The results indicated that PM-2, PM-3 and PM-4 had better degradability on HPAM. PM-4 showed antagonism to two other strains, whereas PM-2 and PM-3 showed synergetic effects. Primary optimized HPAM degradation conditions of mixed PM-2 and PM-3 were 35 °C ~ 45 °C of degradation temperature and 5.5~7.5 of pH. The mixed PM-2 and PM-3 showed alternative in different media and their different growth stage.

The detail and design of numerical control system for SLS are discussed. With the help of Visuall C++ and tool kit ObjectARX in AutoCAD, the data information of the 2D contours are extracted from model in AutoCAD by data processing, and these data are transferred to laser scanning data, finally NC codes for processing are generated. A new kind of adaptive slicing algorithm that determines the slicing thickness by comprehensively considering the surface normal and the cross-sectional area, is adopted in data processing. The preheat temperature, scanning speed, laser power and thickness of spreading layer are main factors to part quality in Selective Laser Sintering(SLS). Sintering parameters are optimized by orthogonal experimental design. And a matching rule between scanning velocity and laser power is established so as to realize the laser power matching in different scanning velocities. In order to maintain and transplanted the system, the modular structure is used in the procedure of system design.

Spline finite strip is the common theoretical analysis method to sheet materials. On the mechanism of cold forming, using spline finite strip theory, characteristic line connection and characteristic finite strip are to build on the reasonableness. Ignored a number of uncertainties, avoided "massive" data, this model simplifies the boundary conditions, improving the system agility. The qualitative factors which are difficult to establish mathematical expression in forming, and the constraint conditions to form model, were tranformed into information description. Combing with specialist experience, solving task system of multi-Agent was established. Then, the dynamic task can be solved by intelligent Agent. This work can provide theoretical guidance for research to sheet materials forming.

Based on mechanism of SLS, the scanning speed, laser power, preheat temperature and thickness of spreading layer are main factors to part quality in Selective Laser Sintering(SLS). With manufactured specimen pieces by Molding machine AFS-450, orthogonal experimental design and analysis of variance were adopted to post-treatment. Three indexes, including sintering strength, constriction percentage and sintering density, were studied. So an optimized project can be determined. This work can provide process parameters in SLS for ABS power. It will be of benefit to improve the part dimensional precision and strength.

Comparing with conventional WEDM in emulsion, dry finishing of high-speed WEDM (HS-WEDM) has advantages such as higher material removal rate, better surface roughness and straightness. Authors have presented a new procedure as gas-liquid combined multiple cut, in which roughing is processed in dielectric liquid, and semi-finishing is in liquid or gas, while finishing is in gas. For better understanding the effect of machining parameters on surface roughness(Ra) and cutting speed (Vw) in dry finishing, a L25(56) Design test was implemented. The analysis of variance shows that offset and wire length are not significant on Ra and Vw. In this paper, the other four significant parameters, such as pulse duration, pulse interval ratio, peak current and no load worktable feed, were selected as factors in Uniform Design test. The final regression equations for Ra and Vw in terms of the actual parameter values were calculated out with MATLAB. Regression statistics of values R2 imply the two regression equtions fit well with test data and Model F-Values imply the two models are significant. Values t and α for regression equation coefficient tests of Ra and Vw show the major impacting items and interactions between them.

The vibrating roller crusher convert relative vibration generated by two rigid bodies to bring high-frequency impulse on grain layer (or granular) in chamber, which makes grain crush to particle. Based on the science of vibration, dynamics model in vibration-impact crushing system of a bilateral single-mass and vibration differential equations are established. By dynamic analysis, amplitude frequency curve, hysteresis impact curve and energy absorption curve are all founded. The curves on dynamic response are discussed. Under the consideration of their results, displacement, velocity and acceleration with the time history are induced. Impact on the left and right sides are unsymmetrical. Influence laws on amplitude frequency, impact, energy absorption from clearance and vibration frequency is also established.

Sintering temperature influences on sintering process essentially. Laser power and scanning speed determined sintering temperature. Preheat to powder is beneficial to improve the surface temperature uniformity. Stress concentration of part is various in different layer depth. Therefore, the influence of laser power, scanning speed, thickness of spreading layer and preheat temperature on part quality in selective laser sintering(SLS) are main factors. Based on laser energy in Gaussian distribution and mechanism of SLS, with manufactured specimen pieces by molding machine AFS-450, orthogonal experimental design and analysis of variance are adopted to post-treatment. The prototyping sintering parameters are optimized. The result and solution of the experiment are the preheat temperature of 100°C, the scanning speed of 2000 mm/s, the laser power of 24W, the thickness of single layer of 0.2mm for ABS resin. This work can provide optimized parameters in SLS for ABS resin. It will be of benefit to improve the part dimensional precision and strength.

Gear-shape error is the key factor to effect driving stability. A analysis on the common gear cutting error processed in hobbing is made, and then the specific reasons for gear-shape error are presented. Finally, the strategies to eliminate the gear-shape error and promote the accuracy of gear machining are gave.

In order to study the breakdown characteristics of oil-paper insulation under compound electric field, the typical oil-pressboard insulation model was adopted according to the insulation structure in converter transformer. The electric field in oil and oil-impregnated pressboard was simulated according to the equivalent circuit for the above model, and the breakdown characteristic test for typical oil-pressboard insulation, oil and oil-impregnated pressboard was carried out separately under compound electric field. To analyze the relationship between the breakdown strength and electric field, the electric field expressions for oil gap and the oil-impregnated pressboard were derived under compound voltage with different AC content. The test result shows that breakdown voltage of oil-pressboard insulation rises first and falls later under compound voltage. According to the characteristics the electric field distribution and breakdown strength of oil gap and oil-impregnated pressboard, it can be found that the breakdown strength of oil-pressboard insulation mainly depends on electric field distribution and breakdown characteristics of oil and oil-impregnated pressboard under compound voltage.

To investigate the age-related expression of KCNQ1 and NKCC1 ion transporters in the stria vascularis in the cochlea of C57BL/6J mice, and to analyze the relationship between the two ion transporters and age-related hearing loss.Auditory function of C57BL/6J mice was measured by auditory brainstem response (ABR) at the ages of 4, 8, 14, 24, 40 weeks old respectively. The location of KCNQ1 and NKCC1 ion transporters in the cochlea of C57BL/6J mice was detected by immunohistochemistry staining. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the levels of KCNQ1 and NKCC1 mRNA in the cochlea of C57BL/6J mice at different ages.The mean values for ABR thresholds in response to click, 4 kHz and 8 kHz sound stimulus of C57BL/6J mice gradually increased with age. The ABR thresholds of the mice of over 14 weeks age were significantly elevated in comparison with lower ages (P0.05). In the lateral wall of C57BL/6J mice cochlea, the KCNQ1 protein was mainly expressed at the apical membrane of the strial marginal cells. The localization of NKCC1 protein was mainly present at the basolateral membrane of the stria marginal cells, spiral ligament and the fibrocytes in the inferior portion of spiral limbus. Expression of KCNQ1 and NKCC1 protein in cochlea of C57BL/6J mice showed age-related decreasing. The level of KCNQ1 and NKCC1 mRNA in cochlea of C57BL/6J also showed a age-related decreasing trend. There was a significant reducing of KCNQ1 mRNA level between C57BL/6J mice of 40 and 4 weeks old (P0.05). In comparison with the C57BL/6J mice of 4 weeks old, the NKCC1 mRNA levels of 24 and 40 weeks old also showed significant reducing (P0.05).The mean value for ABR thresholds of C57BL/6J mice gradually increased with age. Expression of KCNQ1 and NKCC1 protein in the stria vascularis of C57BL/6J mice decreases with age. The levels of KCNQ1 and NKCC1 mRNA in cochlea of C57BL/6J showed a age-related reducing trend. Regulating after post-translation may also participate in the adjusting of the age-related decreasing of KCNQ1 and NKCC1 protein in the cochlea of C57BL/6J mice. KCNQ1 and NKCC1 ion transporters may play a critical role in maintaining normal hearing function of inner ear.

To introduce a novel retractor with magnetic fixator for mouse microsurgery.The retractor was consisted of a magnet, a screw, two screw nuts and a hook made of dental stainless wire. The screw was connected to the magnet with magnetic force, and then was assembled to be a so-called magnetic fixator. The hook was clamped by two screw nuts on the screw, and these makes up of the retractor finally. Comparison has been done between the novel retractor and traditional retractor in the clinical application of the otocyst exposure.The retractor can quickly claw and retract massive tissue like muscles and vessels to the target position, thus, this properties would tend to offer a clear and expanded operative field. In addition, the height, orientation and strength of traction was all adjustable. By Comparison with tradition retractor, the operative incision can be shorten via the application of the retractor, also, it would reduce the trauma of muscles and vessels as well as the accidental rate of bleeding in the process of operation.The retractor can offer a expanded operative field of the mouse otocyst conveniently. It could be a simple, powerful and minimal invasive tool for mouse microsurgery.

To investigate the ototoxicity of co-administration of kanamycin and furosemide in mouse and establish a reliable model to induce a sensorineural hearing loss.CBA/J mice strain was selected, with the age around 3-4 weeks old, to be received a single subcutaneous injection of kanamycin at dose of 1 g/kg and another single intraperitoneal injection of furosemide at dose of 0.4 g/kg 30 - 45 min afterward. The auditory brainstem response (ABR) threshold shift was tested. The series of experimental methods including propidium iodide, phalloidin staining, semithin section toluidine blue staining, TUNEL, scanning electron microscopy and transmission electron microscopy were applied to observe the characteristics of the lesion of cochlea and hair cells. The time course was set as following: before injection, 12, 24, 48 hours and 1, 2, 4, 12 weeks after injections, respectively.The ABR threshold shift was firstly presented a significant increase at 12 h after injection at 2, 4, 8 kHz, then the ABR threshold kept going up during next 36 h until it was presented a stable level around 90 dB. Pathological examination showed an absence of outer hair cells at basal turn rapidly since 12 h after treatment, and then by 48 h the most commonly observed lesion, where all outer hair cells throughout the length of the cochlea were killed, in the contrast, however, the inner hair cells loss were delayed and mild. TUNEL-positive nuclei demonstrated that most hair cells died via an apoptotic pathway. In scanning electron microscopy abundance of necrotic outer hair cells were detected by 24 h after treatment, in which reticular lamina were collapsed. Then all outer hair cells were replaced by expansion of heads of supporting cells. At 48 h after treatment, marginal cells presented a swollen and some of them were observed to be fused. In addition, spherical cell extrusion appeared to leak out from some marginal cells. By 2 weeks, nearly all microvillus were lost and marginal cells presented a shape of stone-like change. A significant and progressive decrease in strial vascularis thickness was found, of which the reason probably related with a reduction in volume of marginal cells.This systemic protocol eliminates hair cells extensively in vivo, and it could be a reliable model to examine different aspects of cochlear pathology in transgenic or mutant mice strains.

To study the expression of plasma membrane Ca(2+)-ATPase isoform 2 (PMCA2) in spiral ganglion cell (SGC) from inner ear of newborn rats and further check PMCA2 splice variants at site A and C.Spiral ganglion tissues isolated from cochlea of newborn rats (P3-P4) were cultured and identified in vitro. The cochlea of newborn rats (P3-P4) were isolated and cut into frozen sections. The expression of PMCA2 was detected by immunofluorescence analyses. The SGC cultured in 4 wells of the 6-well culture plate were collected and the total RNA was extracted by Trizol and reverse transcribed to cDNA. The site A and C splice variants of PMCA2 were respectively checked by nested PCR and common PCR.The SGC grew well with good refraction and showed positive immunoreactivity for neuronal marker NF-200. Strong green fluorescence could be seen in cytomembrane, cytoplasm and neuritis, as well showing SGC immunoreactivity for PMCA2 antibody. In the cochlear sections, the spiral ganglion tissues were strongly stained by PMCA2. PMCA2z was present at splice site A, but PMCA2b and PMCA2c were present at splice site C.SGC from newborn rats strongly expresses PMCA2 and different splice variants are present at PMCA2 splice site A and C.

To achieve the complex forming in open cross-section steel, this thesis established a mechanical model with spline finite strip method based on deformation characteristics of non-uniform division of spline finite strip. It determined the spline area and tie line rationally, simplifies boundary condition in designing pass structure. Aiming at the the impact of qualitative factors shaping which are difficult to quantify, according to specialist experience, theory system of Multi-Agent was established by amending the Agent of knowledge containers and social relationships. This work can provide theoretical guidance for complex design of steel in pass section.