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Background Timely detection of HIV infection is critical for curbing the AIDS epidemic, and building an extensive and effective HIV laboratory network is of great importance. Therefore, improving quality management of the laboratory network and optimizing detection strategies are desirable research issues. Methods We assessed the applicability of the Pareto principle to HIV detection performance. We conducted a retrospective review of basic information and numbers of screening tests among an HIV laboratory network (1,452 laboratories) in Zhejiang province in 2014 and statistically analyzed HIV testing data for different population categories. Results Approximately, 80% of the cumulative HIV screening tests and positive screening tests originated from 17.3% (251/1,452) and 11.7% (170/1,452) of the laboratories in the whole province, respectively, and similar patterns were observed at the prefectural level. We found that the top five population screening categories (25%, 5/20) had the highest contribution (approximately 80%) to not only the number of screening tests (77.2%) but also the numbers of positive (76.4%) and confirmed positive tests (81.5%). Conclusions The Pareto principle provides a method for identifying noteworthy laboratories to deliver prior quality supervision and developing highly efficient screening strategies that best suit local needs., Timely detection of HIV infection is critical for curbing the AIDS epidemic, and building an extensive and effective HIV laboratory network is of great importance. Therefore, improving quality management of the laboratory network and optimizing detection strategies are desirable research issues. We assessed the applicability of the Pareto principle to HIV detection performance. We conducted a retrospective review of basic information and numbers of screening tests among an HIV laboratory network (1,452 laboratories) in Zhejiang province in 2014 and statistically analyzed HIV testing data for different population categories. Approximately, 80% of the cumulative HIV screening tests and positive screening tests originated from 17.3% (251/1,452) and 11.7% (170/1,452) of the laboratories in the whole province, respectively, and similar patterns were observed at the prefectural level. We found that the top five population screening categories (25%, 5/20) had the highest contribution (approximately 80%) to not only the number of screening tests (77.2%) but also the numbers of positive (76.4%) and confirmed positive tests (81.5%). The Pareto principle provides a method for identifying noteworthy laboratories to deliver prior quality supervision and developing highly efficient screening strategies that best suit local needs.

Coenurosis is an important zoonotic helminthic disease caused by the larval stage of the tapeworm Taenia multiceps. This parasite typically infects the brain of the intermediate hosts, including sheep, goat, cattle and even humans. We report a case of T. multiceps infection in a yak confirmed by clinical symptoms, morphological characteristics, and molecular and phylogenetic analyses. The coenurus was thin-walled, whitish, and spherical in shape with a diameter of 10 cm. The parasite species was identified as T. multiceps by PCR amplification and sequencing of the 18S rRNA, cox1 and nad1 genes. Three gene sequences all showed high homology (all above 97%) with the reference sequences from different hosts. Moreover, phylogenetic reconstructions with the 3 published Taenia gene sequences confirmed that the Qinghai yak isolate was closely related to T. multiceps. Although there are advanced diagnosis and treatment methods for coenurosis, early infection is difficult to diagnose. Importantly, the findings of yak infection case should not be ignored due to its zoonotic potential.

Summary Many plant viruses with monopartite or bipartite genomes have been developed as efficient expression vectors of foreign recombinant proteins. Nonetheless, due to lack of multiple insertion sites in these plant viruses, it is still a big challenge to simultaneously express multiple foreign proteins in single cells. The genome of Beet necrotic yellow vein virus (BNYVV) offers an attractive system for expression of multiple foreign proteins owning to a multipartite genome composed of five positive‐stranded RNAs. Here, we have established a BNYVV full‐length infectious cDNA clone under the control of the Cauliflower mosaic virus 35S promoter. We further developed a set of BNYVV‐based vectors that permit efficient expression of four recombinant proteins, including some large proteins with lengths up to 880 amino acids in the model plant Nicotiana benthamiana and native host sugar beet plants. These vectors can be used to investigate the subcellular co‐localization of multiple proteins in leaf, root and stem tissues of systemically infected plants. Moreover, the BNYVV‐based vectors were used to deliver NbPDS guide RNAs for genome editing in transgenic plants expressing Cas9, which induced a photobleached phenotype in systemically infected leaves. Collectively, the BNYVV‐based vectors will facilitate genomic research and expression of multiple proteins, in sugar beet and related crop plants.

On January 25, 2017, a physician from ZC Hospital in Hangzhou, China, reported to the Zhejiang Provincial Center for Disease Control and Prevention that a potential HIV outbreak might have occurred during lymphocyte immunotherapy (LIT) performed at the hospital on December 30, 2016. We immediately began investigating and identified the index case-patient as an LIT patient’s husband who donated lymphocytes for his wife’s LIT and later screened HIV-reactive. Subsequent contamination by a technician resulted in the potential exposure of 34 LIT patients. Acute HIV infection was diagnosed in 5 persons. Phylogenetic analysis confirmed that the HIV-1 gag, pol, and env gene sequences from the index and outbreak-related cases had >99.5% similarity. Rapid investigation and implementation of effective control measures successfully controlled the outbreak. This incident provides evidence of a lapse in infection control causing HIV transmission, highlighting the need for stronger measures to protect patients from infectious disease exposure.

In recent years, the population of men who have sex with men (MSM) constitute a major group for HIV transmission in China. A total of 340 newly reported HIV-infected MSM were recruited proportionally from ten prefectures across Zhejiang province between January and December in 2013. Partial pol gene was amplified and sequenced. Phylogenetic relationship, transmission network and genotypic drug resistance analyses were performed on 311 sequences. HIV-1 subtypes including CRF01_AE (55.9%), CRF07_BC (37.6%), subtype B (1.9%), CRF55_01B (1.3%), CRF68_01B (0.3%), CRF08_BC (0.3%) and URFs (2.6%) were identified. A higher proportion of CRF07_BC and other subtypes existed in the >35 years group, while a higher proportion of CRF01_AE was present in the young group (

The unlubricated sliding wear test of high chromium white cast irons (HCCIs) was conducted using a pin-on-disc configuration under different heat treatments and different hardnesses of the counterface. With the increase of counterface hardness (20 HRC–47 HRC–54 HRC), the mass loss of the sample first increases then decreases. When the counterface hardness is 20 HRC, adhesion wear mainly takes place between the high chromium cast iron and the surface of 1045 steel. When the hardness is 47 or 54 HRC, first HCCI’ matrix wear takes place, then carbide bump flakes under alternating stress. The mass loss of the counterface decreases with the increase of hardness for the same sample. The mass loss of quenching, once tempering and twice tempering sample decreases gradually for the same counterface hardness, but fluctuation of the samples’ surface increased. The disc material is always softer than the pin material and results in a severe wear regime operation.

In this study, to improve the interfacial bonding between the inner sleeve and outer layer of a duplex roller sleeve, a model of the uphill casting of a roll sleeve was constructed with a commercially available process modeling software and simulated the temperature fields in the casting process. Furthermore, the effects of the pouring temperature, the preheating temperature of the steel sleeve and the preheating temperature of the sand on the boundary temperature between the casting and 1045 steel sleeve were simulated. The results show that the lower boundary temperature (1268 °C) between the casting and 1045 steel sleeve leads to poor bonding strength because the metallurgical bonding layer does not form. Increasing the pouring temperature (1450–1600 °C), the preheating temperature of the steel sleeve (600–1200 °C) and the preheating temperature of the sand (60–260 °C) can increase the boundary temperature, which favors the formation of a metallurgical bonded layer and enhances the bonding strength between the casting layer and 1045 steel sleeve. Finally, 1550 °C pouring temperature, and the preheating temperature of the inner sheath and casting sand of 1000 and 160 °C, respectively, are adopted in casting a roll sleeve, when other conditions remain unchanged. The results of the samples collected in the middle of the casting suggest that the maximum surface temperature of the inner sheath should be above the solidus temperature and a metallurgical bonded layer will form.

Compound casting consists of two techniques: horizontal centrifugal casting and gravity filling casting. In this study, a numerical model was developed for compound casting of multilayered multiple-metal cast rolls, and a 500-mm CR4 casting roll was simulated. In the simulation, the process of compound casting was divided into three stages and the development of filling flow, solidification of melt and evolution of temperature field in each stage was computed with the model. The model was then verified by comparison of (1) the simulation result with the measured temperature history on the surface of a 500-mm CR4 casting roll produced in a test process and (2) the simulated temperature history of the CR4 layer with the measured CCT (continuous cooling transformation) diagram of CR4 material. The simulation results in different stages of compound casting are also discussed for improving casting process design and defect preventing. The lower temperature at the location 15 mm away from both ends on the inner surface of the CR4 layer could cause poor merging with the intermediate layer.

The variations of microstructure and mechanical properties of a high-chromium cast iron for rolls were studied from as-cast to the final heat treatments. Results show that the as-cast microstructure of the HCCI consists of M7C3carbide, M23C6carbide, martensite matrix, and retained austenite. The large dendritic M7C3carbide surrounds the matrix, and the M23C6carbide is mainly distributed in the matrix. Part of M23C6carbide transforms to M7C3carbide and is dissolved in austenite during austenization at 1020°C. Thus, the amount of M23C6carbide decreases, whereas that of M7C3carbide increases after quenching; the highest hardness is also obtained. After tempering, the martensite transforms to a tempered martensite, and some carbide precipitates in the martensite matrix. The hardness also changes from HRC62.1, which corresponds to quenching, to HRC55.2 and HRC56.3, which correspond to once and twice tempering, respectively. However, tempering could improve the impact toughness and wear resistance of the HCCI.

Transmission line is an important part of smart grid, evaluating the state of transmission line effectively and comprehensively has a great significance to the grid. First, this paper collects all basic parameters of transmission line through guidelines, standards, operation manuals and related files from China State Grid. Then, we establish the key parameter system for condition assessment using the principal components analysis (PCA) method based on the records of faults, failure, maintenance and standard database. Then, the fuzzy theory is used for the state evaluation by combining analytic hierarchy process (AHP) method and entropy weight method in order to enhance the impact of the indicator’s changes in magnitude on the weights. Finally, we verify the validity of the method by evaluating the condition of the known power transmission line.

To clone and express the Tibetan Sheep-origin Echinococcus granulosus Antigen B8/2 Gene, and immunologically identify the encoded protein.The cDNA of EgAgB8/2 gene was amplified by RT-PCR. The prokaryotic expression vector pET-EgAgB8/2 was constructed and transformed into E. coli BL21（DE3） for expression. Proteins were extracted, separated in SDS-PAGE and identified by Western blotting.The cloned EgAgB8/2 gene was 335 bp in length, and had a 98%-100% sequence homology with the reported cDNA sequence of EgAgB8/2, indicating the successful construction of the pET-EgAgB8/2 vector. SDS-PAGE revealed large amount of proteins in supernatant. Western blotting further confirmed the expression of the target protein.The EgAgB8/2 gene of Tibetan Sheep-origin in Qinghai is successfully cloned, and the constructed pET-EgAgB8/2 vector can be used to express the target protein.

HIV transmitted drug resistance (TDR) can compromise antiretroviral therapy (ART) in resource-limited countries like China where ART has been scaled up and thus leads to an important public health concern. The aim of the study was to elucidate the HIV-1 genetic characteristics and TDR in Hangzhou, China. Two-hundred eleven ART-naive, newly diagnosed individuals were enrolled during January and August 2013. Specimens were classified as recent or chronic infections using the BED capture enzyme immunoassay (BED-CEIA). The pol fragment covering the entire protease and the first 300 codons of the reverse transcriptase gene was amplified by RT-PCR and nested PCR. Genotypic drug resistance (DR) and phylogenetic analysis were performed on the 200 obtained sequences. Multiple genotypes were identified, including CRF01_AE (62.0%), CRF07_BC (31.0%), subtype B (2.0%), CRF08_BC (1.5%), CRF55_01B (1.0%), CRF18_cpx (0.5%), and unique recombinant forms (URFs, 2.0%). All the four URFs were found in men who have sex with men, consisting of a recombination of CRF01_AE with subtype B or CRF07_BC. The prevalence of primary DR in newly diagnosed individuals in Hangzhou was low (4.0%). The proportion of DR mutation to protease inhibitors (PIs), nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs) was 1.5%, 1.5%, and 1.0%, respectively. BED-CEIA revealed that 21.8% (45/211) of the specimens were associated with recent infections. The prevalence of TDR in recent infections was moderate (6.5%). High HIV diversity and relatively high prevalence of TDR in new infections has been found in Hangzhou, indicating an increasing challenge for future HIV prevention and treatment. J. Med. Virol. 87:1668–1676, 2015. © 2015 Wiley Periodicals, Inc.

The epidemic characteristics of human immunodeficiency virus type 1 (HIV-1) in Zhejiang Province have not been systematically identified. This study presented a dynamic analysis of HIV-1 subtype variation in Zhejiang from 2004 to 2008, based on the surveillance of molecular epidemiology or drug resistance. CRF01_AE was the major strain (43.5 %) spreading across the province, second by B/B' (17.9 %), CRF07_BC (17.1 %), and CRF08_BC (13.7 %). The strains were mainly transmitted by heterosexual contact. Novel recombinant strains and vertical transmission were occasionally reported. Floating population from other provinces accounted for a significant number of HIV-1 cases in Zhejiang. These data may provide us rational intervention strategy for further control of HIV dissemination.

Infection of boar-hunting dogs with Paragonimus westermani was investigated in Western Japan. Blood and rectal feces were collected from 441 dogs in the three districts (205 in Kinki, 131 in Chugoku and 105 in Shikoku District). In a screening ELISA for serum antibody against P. westermani antigen, 195 dogs (44.2%) showed positive reaction. In the 195 dogs, 8 dogs were found excreting P. westermani eggs after molecular analysis of fecal eggs, and additional 7 were identified serologically for the parasite infection because of their stronger reactivity against P. westermani antigen than against antigens of other species of Paragonimus. A spatial analysis showed that all of the P. westermani infections were found in Kinki and Chugoku Districts. In this area, dogs’ experience of being fed with raw boar meat showed high odds ratio (3.35) to the sero-positivity in the screening ELISA, and the frequency of such experiences was significantly higher in sero-positive dogs. While clear relationship was not obtained between predation of boars by dogs during hunting and their sero-positivity. Therefore, it is suggested that human activity of feeding with wild boar meat is the risk factor for P. westermani infection in boar-hunting dogs. Considering that hunting dogs could play as a major definitive host and maintain the present distribution of P. westermani in Western Japan, control measures for the infection in hunting dogs, such as prohibition of raw meat feeding and regular deworming, should be undertaken.

To investigate the HIV-1 molecular epidemiology among young people (18 to 25 years old) in Hangzhou. Plasma samples from 262 newly diagnosed HIV-1-infected patients were collected between 2009 and 2013 from Hangzhou of Zhejiang province. HIV-1 nucleotide sequences of pol gene regions were amplified using a nested polymerase chain reaction method and sequenced. Phylogenetic and recombination analyses were used to determine the HIV-1 genotypes. Based on all sequences generated, the subtype/circulating recombinant forms (CRFs) distribution was as follows: CRF01_AE (68.70%), CRF07_BC (21.54%), subtype B (3.66%), CRF08_BC (2.44%), 01B (2.03%), BC (0.81%), and C (0.41%). We found that the percentage of CRF07_BC was increasing year by year among young people in Hangzhou. Novel CRFs such as CRF67_01B (HZ2011-15 CD4-4516) and CRF68_01B (HZ2011-20 CD4-4530 and HZ2011-29 CD4-4087) were first discovered in the area in this study. Our study presents a molecular epidemiology investigation describing the structure of HIV-1 strains cocirculating in young people in Hangzhou. Increasing CRF07_BC and new CRFs popular in young people are a challenge for future prevention in Hangzhou.

Fatigue has a serious influence on people’s production and life. In this paper, which using the discrete Fourier transform algorithm to segment and extract person's facial image, so we can have a effective monitoring of people’s fatigue state base on the facial characteristic. With the help of the parameters characteristic of the Fourier transform, we can extract the key facial information from the image and achieve accurate position of the eyes. Simulation results show that the use of discrete Fourier transform to the exact position of the human eye, having a greatly improve on the operation speed of the eyes position system, and improving its accuracy and robustness.

Thermal stability can reflect the thermal degradation speed of polymers during the melt processing. In this paper, we used Kissinger, Flynn-Wall-Ozawa and Coats-Redfern method to study the kinetics of non-isothermal degradation of PFA. The thermal degradation activation energy obtained from the Kissinger method, Flynn-Wall-Ozawa method and Coats-Redfern method is 228.5 kJ/mol, 213.9 kJ/mol and 237.4 kJ/mol respectively. The Flynn-Wall-Ozawa method indicates the thermal degradation reaction PFA is a secondary reaction.

This review summarizes microbial translocation in HIV infection. Microbial translocation can be measured by bacterial products in plasma, such as LPS and bacterial DNA or RNA fragments, or indirectly by LBP, sCD14, EndoCAb, and antiflagellin antibodies. In some study, these markers had contrary results. May be microbial translocation is not the sole driver of HIV progression. Several lines of research indicated that a major contributor to immune activation and disease progression during HIV infection was microbial translocation. Although successful treatment with ART increased GALT CD4+ T cells and suppresses HIV RNA, the numbers of these cells did not return to prior levels. There is a negative effect of mucosal immune dysfunction and microbial translocation on HIV disease progression in the presence of ART. The topic of microbial translocation and immune activation in HIV infection still is a research focus.

Capillary rheometer was used to conduct preliminary study on the rheological behavior of SKYPEL thermoplastic polyester elastomer (TPEE). SKYPEL TPEE is a kind of non-Newtonian fluid and displays typical shear thinning behavior. Non-Newtonian index of the three samples varies from 0.69 to 0.77. With increasing temperature, the structure viscosity of the sample decreased and among them G172D is the smallest one under the same temperature.

The impact performance of PE can be greatly enhanced by the use of functionalized conch powder, while maintaining high tensile strength thus giving this study high potentiality for its practical applications. The conch powder was treated by titanate coupling agent NDZ-201 before use and the influence of different proportions of conch powder on the mechanical properties of PE/conch powder composite is discussed in this article. The impact strength has a maximum value of 63.4kJ/m2 and the frictional loss records a minimum of 4.27×10-1mm3/(Nm)-1 and 42.2% lower than that of pure PE.

A new high-strength magnesium alloy with better properties than that of AZ31 was developed. The effect of applied pressure during squeeze casting on microstructures and properties of the alloy was studied by means of techniques such as standard mechanical tester, Brinell Hardness Tester (BHT), and Metallographic Microscope (MM). The parameters studied include squeeze casting pressure, melt temperature and pressure holding time by using orthogonal experimental method. It was found that a squeeze casting pressure of 110 MPa and a melt and pressure holding time of 700 °C and 15s respectively gave a good combination of mechanical properties in AZ31 Mg alloy. This was primarily due to effective die filling, microstructural refinement and good heat transfer between the molten metal and the mould.

The non-isothermal crystallization process of PBT with high melt flow index has been investigated by DSC, and the nonisothermal crystallization process of PBT with high melt flow index was studied by Ozawa equation and Jeziorny equation respectively. It was found that Ozawa equation, rather than Jeziorny equation, could appropriately be applied to study the non-isothermal crystallization process of PBT with high melt flow index. The Avrami index, obtained by Ozawa equation, varied between 1.06-1.80 with the change in temperature.

Polyoxymethylene is a linear polymer with excellent performance due to its chemical structure and high crystallinity. The thermal and rheological properties of POM are investigated in this paper. Experimental results indicate that the melting point and decomposition temperature of POM are about 162 °C and 266 °C respectively. POM melt is a non-Newtonian fluid, the apparent viscosity gradually decreased with the increase of shear rate, showing a typical shear-thinning behavior. Non-Newtonian index increased from 0.53 to 0.61 as the melt temperature increased from 190 °C to 230 °C. The flow activation energy of POM melt is between 11.36 and 24.90 kJ/mol within the shear rate range of 90~2500s -1.

Melt-blown generated PBT nonwoven fabrics usually have small fibril diameter, high flexibility, well heat and oil resistance. Therefore, they would have promising application such as vehicle filtering media. The rheological behavior of PBT with High Melt Flow Index for Melt-blown is investigated in this paper. It is a direction of the technology design and fabrication parameters .The relation of apparent viscosity and shear rate is analyzed, as well as flow activation energy and Non-Newtonian indexes. The results suggest that PBT with High Melt Flow Index is Non-Newtonian fluid. Apparent viscosity and flow activation energy show gradually decrease with increasing shear rate, exhibiting typical shear-thinning behavior.

The squeeze cast process parameters of AZ80 magnesium alloy were optimized by morphological matrix. Experiments were conducted by varying squeeze pressure, die pre-heat temperature and pressure duration using L 9 (3 3 ) orthogonal array of Taguchi method. In Taguchi method, a 3-level orthogonal array was used to determine the signal/noise ratio. Analysis of variance was used to determine the most significant process parameters affecting the mechanical properties. Mechanical properties such as ultimate tensile strength, elongation and hardness of the components were ascertained using multi variable linear regression analysis. Optimal squeeze cast process parameters were obtained.

Low-temperature performance of LiBF4 and LiPF6-based electrolytes in LiFePO4/Li and graphite/Li half cells was investigated. In the temperature range from 0 °C to −40 °C, electrochemical impedance spectroscopy (EIS) results show that the charge-transfer resistance (Rct) of graphite/Li cell decreases, the Rct of LiFePO4/Li cell increases, and sum resistance of LiFePO4/Li and graphite/Li cell decreases when replacing LiPF6 with LiBF4. In the temperature range from 25 °C to −40 °C, energy barrier (W) for Li-ion jump at the solid electrolyte interface (SEI) alters slightly from 16.04 kJ/mol to 13.60 kJ/mol in LiFePO4/Li cells, but declines greatly from 46.47 kJ/mol to 19.81 kJ/mol in graphite/Li cells when using LiBF4 instead of LiPF6, meanwhile, activation energy (ΔG) of electrode reaction is approximately the same (∼60 kJ/mol). The above results indicate that the ionic conductivity is the main limiting factor for low-temperature performance of electrolytes in LiFePO4/Li cell, while factors related with electrolyte-interface are more crucial in graphite/Li cell than in LiFePO4/Li cell.

A research program was simulated to study the effects of pouring temperature, squeeze pressure and die temperature on the tensile, elongation and hardness properties of AZ91D magnesium alloys using anycasting software. The curves with different processing parameters on mechanical properties have been painted. The results indicated that mechanical properties increased firstly, then decreased when the pouring temperature increased to 670°C, and gradually increased with the increasing of squeeze pressure. The affect laws of mould temperature are similar as ones of pouring temperature. Eventually found that the squeeze casting got better mechanical properties(σb= 225MPa, δ= 3.6%, Vickers hardness=62) on the pouring temperature 670°C, mold temperature 180°C, holding pressure 120Mpa, pressure duration 25s.

Carry on unattended substation at the voltage of 220kV and the following is a technological innovation which having the profound influence to the current power supply system, is also the most important technology safeguard measure of the downsizing for efficiency in the power supply system. Along with the development of modern communication technology, computer technology, network technology, automatic control technology, image technology, monitoring technology and weak electricity integration technology, we had already realized the image and the sound signal's digitization, the audio and video signal's processing and the long-distance transmission. To the substation, besides the remote measurement, the remote signaling, the remote control, and the remote regulating functions which have already realized, the remote monitoring has also increased which called “five remote”. The “five remote” caused unattended substation become the reality and give a higher request to the information management and the intellectualization simultaneously. According to many years unattended substation's operational guidance experience, I proposed my ideas about the information management and the intellectualization of unattended substation, I hope that it is helpful to the promotion of the unattended substation.

We have designed IIR (Infinite Impulse Response) lowpass digital filters based on Butterworth and Chebyshev approximations, and conducted an experiment research of filtering to GT-1A airborne gravity data. The result shows that: by selecting proper parameters such as passband and stopband attenuation, these IIR lowpass digital filters for airborne gravity data can get satisfactory filtering effect almost as good as that of GT-1A filtering result.

Tensile behaviors of extruded and rolled AZ80 Mg alloy were investigated with elongation-to-failure tensile tests at constant temperatures of 300 °C, 350 °C, 400 °C, and 450 °C, and constant strain rates of 10-2 s-1 and 10-3 s-1. Experimental data show that the material exhibits tensile ductilities of over 100% at 400 °C and 450 °C, featured by long steady state deformation. Microstructure studies show that annealed coarse grains were remained in the gauge region during the tensile tests, and the enhanced tensile ductilities resulted from dislocation creep, other than dynamic recrystallization or grain boundary sliding. Cavity evolution and recrystallized coarse grains near fracture end caused premature failure of the material.

The corona characteristic of HVDC tube bus is the main factor taken into account for choosing tube bus of HVDC converter substation. The intension of corona could affect the electromagnetic environment of converter station and generate audible noise. By establishing the calculation models of electric field strength along the tube bus surface and the electric field strength on ground, the paper computes the corona onset voltage gradient and gives the relation curve of high and electrode spacing of tube bus. If the tube bus in HVDC converter substation is installed at the high and electrode spacing, got by the relation curve, it will not generate corona and its electric field strength will meet the requirements. The control indexes of tube bus corona characteristic parameters for HVDC converter substation are confirmed in combination with calculation results and related standards. Based on the control indexes, the paper gives the collocations of different tube bus types.

In order to quantitatively evaluate the performance index of airborne gravity system, repeated flight lines are usually used to test the coherence of dynamic survey of airborne gravimeter. However, there is no corresponding criterion in the current code to evaluate the quality of repeat line test data of airborne gravity survey. We research and summarize a method of RMS (root mean square) accuracy calculation for the test data of repeat lines. Based on the calculation results of internal and external accord accuracy, we can objectively evaluate the dynamic accuracy index and working status of the instrument.

To improve its visible light response capability, a new narrow bandgap zinc ferrite semiconductor was in-situ introduced into the matrix of titanium dioxide nano film. ZnFe2O4 doped TiO2 composite films have been successfully formed on glass and stainless steel substrates from aqueous solution through equilibrium reaction between iron (III)-titanium (IV)-fluoric complex and boric acid, followed by in-situ hydrothermal conversion and crystallization in the Zn2+-contained basic environment. The obtained films were densely packed and had no visible cracks; clear photovoltaic responses were observed in the anodic direction, and they were much larger in the presence of ferrite dopant. It is suggested that the shift of the corrosion potential was ascribed to photo-induced charge separation between the conduction band of ZnFe2O4 and its counterpart TiO2 nano-particles.

TiO2 is one kind of semiconductor-based photocatalyst. TiO2 shows relatively high reactivity and chemical stability under ultraviolet (UV) light. However TiO2 is a poor absorber of photons in visible light. In order to improve the absorption efficiency, the coatings of TiO2/WO3, WO3 and TiO2 on ITO were prepared by liquid phase deposition (LPD) and dip coating method, their microstructure, surface properties, photoelectrochemical properties are investigated in this paper. XRD results showed that the phases on the composite coatings are mainly anatase, rutile and WO3 respectively, the SEM results showed that the coatings of TiO2 and TiO2/WO3 are distributed evenly on the materials surface. The electrochemical experiment results showed that open circuit potential of TiO2 and TiO2/WO3 with presence of the UV light illumination were about -343 mV and –650 mV respectively, comparatively the rest potential of 304 stainless steel is about 48 mV, which means that the TiO2 or TiO2/WO3 coatings can protect 304 stainless steel from corrosion, and TiO2/WO3 coatings retained for a while anticorrosion even absence of UV light.

The objective of this article was to investigate the morphological and molecular characterization of Oestromyia leporina (Pallas, 1778) from wild plateau pikas (Ochotona curzoniae) in Qinghai province, China. The third-stage larvae of O. leporina were examined by scanning electron microscopy revealing morphology characteristics of the spines on the cephalic, the thoracic segments, the abdominal segments and the spiracular plates. The coding regions of 25 cytochrome oxidase I (COI) genes of O. leporina were investigated. Eighty-one variable sites and 21 haplotypes were identified and the nucleotide and haplotype diversities were 0.04456 and 0.9767, respectively, indicating a rich genetic diversity in O. leporina. Phylogenetic analysis utilizing sequences of COI revealed two distinct lineages. These findings revealed ultrastructure and molecular characterization among the O. leporina from plateau pikas in Qinghai province, China and had implications for studying morphological identification, molecular epidemiology and population genetics of O. leporina.

Gridding of irregularly distributed potential field data is one of the first and most crucial steps in data analysis. This paper brings forward to realize the gridding of potential field data by using inverse interpolation based on the preconditioning conjugate-gradient iterative algorithm. The gridding method adopts Gaussian weighted coefficients as the interpolation operator, Laplacian operator as the smooth filter, and the inverse of the smooth filter as the preconditioning operator. Experimental results on the synthetic model and the raw aeromagnetic data show that the method is suitable for the features of geophysical potential field, and is a computationally efficient and robust 2-D method with high accuracy and perfect effects.

For the first time we point out that the analytic odd points in upper non-source semi-space, where the value cannot be obtained, exist in original forward theoretical expressions of total field ∆T and its gradients of cuboid. Through detailed formula deduction and discussion on the cause why analytic odd points exist, we deduce new forward theoretical expressions of total field T and its gradients of cuboid without analytic odd points in upper non-source semi-space. Comparison of forward calculation of models shows that these new expressions are proved to be correct.