38 results on '"Zhang, Qingfeng"'
Search Results
2. A 7-nt nucleotide sequence variant within the sheep KDM3B gene affects female reproduction traits
- Author
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Yuxin Kang, Yi Bi, Chuanying Pan, Xianyong Lan, Xu Hongwei, Qi Tang, and Zhang Qingfeng
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0301 basic medicine ,Genetics ,Candidate gene ,Lysine ,0402 animal and dairy science ,Nucleic acid sequence ,Bioengineering ,04 agricultural and veterinary sciences ,Biology ,complex mixtures ,040201 dairy & animal science ,03 medical and health sciences ,Histone H3 ,030104 developmental biology ,Histone ,biology.protein ,bacteria ,Demethylase ,Animal Science and Zoology ,Gene ,Biotechnology ,Demethylation - Abstract
Lysine demethylase 3B (KDM3B) gene is a histone demethylase, demonstrating specific demethylation of the histone H3 lysine 9. It was detected as a sheep reproductive candidate gene by genome-wide s...
- Published
- 2021
3. A 24-bp indel within the sheep AHR gene is associated with litter size
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Hongying Ren, Tao Xue, Chuanying Pan, Qi Tang, Qian Wang, Xu Hongwei, and Zhang Qingfeng
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0301 basic medicine ,Genetics ,Litter (animal) ,biology ,Cell growth ,0402 animal and dairy science ,Bioengineering ,04 agricultural and veterinary sciences ,Aryl hydrocarbon receptor ,040201 dairy & animal science ,03 medical and health sciences ,030104 developmental biology ,Immune system ,Polymorphism (computer science) ,biology.protein ,Animal Science and Zoology ,Indel ,Gene ,Biotechnology - Abstract
Aryl Hydrocarbon Receptor (AHR) is a member of the PER-ARNT-SIM (PAS) family, which could mediate various biological processes, for instance, the balance of the immune system, cell proliferation, d...
- Published
- 2021
4. Seventy Shades of Grey—Office Space Design of Wuhan Yiyang
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Zhang Jingtao and Zhang Qingfeng
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Geography ,Space (commercial competition) ,Cartography - Published
- 2021
5. Relationships between novel nucleotide variants within the colony-stimulating factor 1 receptor (CSF1R) gene and mastitis indicators in sheep
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Chuanying Pan, Xianyong Lan, Zhang Qingfeng, Huina Hu, and Yuta Yang
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0301 basic medicine ,chemistry.chemical_classification ,Genetics ,Innate immune system ,0402 animal and dairy science ,Bioengineering ,Inflammation ,04 agricultural and veterinary sciences ,Biology ,medicine.disease ,040201 dairy & animal science ,CSF1R gene ,Mastitis ,Colony stimulating factor 1 receptor ,03 medical and health sciences ,030104 developmental biology ,chemistry ,medicine ,Animal Science and Zoology ,Nucleotide ,medicine.symptom ,Receptor ,Biotechnology - Abstract
Colony-stimulating factor 1 receptor (CSF1R) plays an important role in the process of innate immunity and inflammation, thus it was hypothesized that the CSF1R gene might affect the occurrence of ...
- Published
- 2020
6. Detection of the 23-bp nucleotide sequence mutation in retinoid acid receptor related orphan receptor alpha (RORA) gene and its effect on sheep litter size
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Cui Mao, Yuta Yang, Lu Xiaofang, Han Xufei, Chuanying Pan, Jiang Fugui, Xianyong Lan, Huina Hu, Hao Kunjie, and Zhang Qingfeng
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Genetics ,Orphan receptor ,Genotype ,Nucleic acid sequence ,Intron ,Animal Science and Zoology ,Bioengineering ,Heterozygote advantage ,Locus (genetics) ,Biology ,Indel ,Gene ,Biotechnology - Abstract
Retinoid acid receptor related orphan receptor alpha (RORA) transcribes steroid-related genes to regulate estrogen synthesis. As an important reproductive trait, litter size relates to estrogen synthesis. Therefore, it is important to investigate the association between RORA gene and sheep litter size. In this study, one 23-bp nucleotide sequence mutation was identified in intron 1 of RORA gene in 532 female Australian White Sheep. Moreover, the polymorphic information content (PIC) values of this locus was 0.219. The litter size of ID genotype was significantly better than II genotype and DD genotype in the second born litter size (p < 0.05). This loci was related to third born litter size and the ID is the dominant genotype (p < 0.05). The association between combined genotypes and average litter size showed that sheep with heterozygote (ID) genotypes had larger lamb than homozygous (DD and II) genotypes. To sum, this study provided theoretical references for the comprehensively research of the function of RORA gene and the breeding of Australian White Sheep. The 23-bp indel variants could be considered as molecular markers for the second and third born litter size of sheep for MAS breeding.
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- 2020
7. Whole-genome sequencing of Chinese native goat offers biological insights into cashmere fiber formation
- Author
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Wei-Dong Deng, Wei Qiang, Wang Ran, Bater Wulan, Zhang Qingfeng, Hu Han, Bin Li, Xing-Ju Zhang, Yang Manman, Chen Tao, Ting-Ting Zhang, Qi-Ju Wang, Lin Li, Cheng-Ye Yang, Miao Zepu, Gang Gen, Mengkedala, Fang Ming, Sheng-Yu Chao, Jiang Dan, and Yong Li
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Molecular breeding ,Whole genome sequencing ,Genetics ,Candidate gene ,medicine.anatomical_structure ,medicine ,Cashmere goat ,Biology ,Selective sweep ,Hair follicle ,Gene ,Genetic association - Abstract
Cashmere evolved naturally in the goat, and almost all breeds of goat can produce more or less cashmere fibers. However, the genetic alterations underlying cashmere trait selection are still unclear.We sequenced 120 Chinese native goat including two cashmere goat breeds (Ujumain, Chaidamu) and six ordinary goat breeds (Jining Gray, Matou, Guizhou Black, Jintang Black, Yunnan Black Bone, Chengdu Brown). The genome-wide selective sweep of cashmere goat and ordinary goat revealed a novel set of candidate genes as well as pathways, such as Nuclear factor kappa-B and Wnt Signaling pathways. Of them, theLHX2gene regulating hair follicle development, was evident from the strongest selection signal when comparing the Uhumqin cashmere goat and ordinary goat. Interestingly, we identified a 582bp deletion at 367 kb upstream ofLHX2with higher frequency in cashmere goats and their ancient relatives. This mutation probably rises along the breeding procedures, and is putatively responsible for cashmere production and diameter, as revealed by association studies. Luciferase assay shows that the deletion, which acts as an insulator, restrains the expression ofLHX2by interfering its upstream enhancers.Our study discovers a novel insulator of theLHX2involved in regulating cashmere production and diameter, which would be beneficial to understanding hair follicle development and regeneration. Our findings also provide new insights into the genetic formation of cashmere, and facilitate subsequent molecular breeding for cashmere goat improvement.
- Published
- 2021
8. Evaluation of left ventricular function by treadmill exercise stress echocardiography combined with layer-specific strain technique in essential hypertension patients
- Author
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Zhang Qingfeng, Wang Yi, Li Wenhua, Zhang Hongmei, Ding Geqi, Liu Xuebing, Li Chunmei, Deng Yan, and Yin Lixue
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Ventricular Dysfunction, Left ,Echocardiography ,Endocrinology, Diabetes and Metabolism ,Hypertension ,Internal Medicine ,Humans ,Essential Hypertension ,Cardiology and Cardiovascular Medicine ,Ventricular Function, Left ,Echocardiography, Stress - Abstract
The purpose of this study was to evaluate the diagnostic utility of treadmill exercise stress echocardiography (TESE) combined with left ventricular (LV) layer-specific strain (LSS) in subclinical myocardial and reserve function of hypertensive patients. A total of 55 hypertensive patients and 51 controls were evaluated during rest and exercise. Two-dimensional speckle tracking (2DST) and LSS technique was used to measure longitudinal and circumferential strains at rest and peak exercise, strain difference characteristics were then evaluated. Compared to the control subjects, both longitudinal and circumferential LSS showed different degrees of reduction in hypertensive group, which was more pronounced at peak exercise. The global longitudinal endocardium strain (GLSendo) at rest was 24.4% ± 1.5% in the control group versus 20.4% ± 2.3% in the hypertensive group, while the difference was more obvious at peak state (control vs. hypertensive group, 30.8% ± 2.8% and 22.8% ± 2.9%, respectively). In particular, endocardial strain under exercise can be used as a sensitive indicator where the LV contractile reserve (CR) function of the three layers are all impaired. TESE combined with LSS might increase diagnostic accuracy of myocardial performance in hypertension patients.
- Published
- 2021
9. Dynamic Characteristics of a Boiler with Low-NOX Combustion
- Author
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Lin Yang, Shi Yang, Zhao Zhenning, Zhang Qingfeng, Li Yuanyuan, and Li Jinjing
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Waste management ,Environmental science ,Combustion ,NOx ,Boiler (water heating) - Published
- 2021
10. Relationship between an indel mutation within the SIRT4 gene and growth traits in Chinese cattle
- Author
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Zhang Qingfeng, Jiang Fugui, Yunyun Jin, Wang Yafang, Xianyong Lan, Cheng Haijian, and Enliang Song
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0301 basic medicine ,Genetics ,medicine.medical_specialty ,Animal production ,0402 animal and dairy science ,Bioengineering ,04 agricultural and veterinary sciences ,Biology ,040201 dairy & animal science ,03 medical and health sciences ,030104 developmental biology ,Livestock farming ,Molecular genetics ,Sirtuin ,medicine ,biology.protein ,Animal Science and Zoology ,Gene ,Beta oxidation ,INDEL Mutation ,Biotechnology - Abstract
Growth traits are mainly determined by genetic factors. SIRT4, a class II sirtuin, predominantly acts as an ADP-ribosyltransferase and inhibits fatty acid oxidation. In this study, a total ...
- Published
- 2019
11. Comparative Analysis of Fractional Vegetation Cover Estimation Based on Multi-sensor Data in a Semi-arid Sandy Area
- Author
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Zhang Ting-long, LI Yi-zhe, Li Ying, BU Chongfeng, Liu Qiu-yu, and Zhang Qingfeng
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Coefficient of determination ,010504 meteorology & atmospheric sciences ,Mean squared error ,Pixel ,Geography, Planning and Development ,Multispectral image ,Regression analysis ,010501 environmental sciences ,01 natural sciences ,Normalized Difference Vegetation Index ,Approximation error ,General Earth and Planetary Sciences ,Satellite imagery ,0105 earth and related environmental sciences ,Remote sensing - Abstract
The estimation of fractional vegetation cover (FVC) is important for identifying and monitoring desertification, especially in arid and semiarid regions. By using regression and pixel dichotomy models, we present the comparison of Sentinel-2A (S2) multispectral instrument (MSI) and Landsat 8 (L8) operational land imager (OLI) data regarding the retrieval of FVC in a semi-arid sandy area (Mu Us Sandland, China, in August 2016). A combination of unmanned aerial vehicle (UAV) high-spatial-resolution images and field plots were used to produce verified data. Based on a normalized difference vegetation index (NDVI) regression model, the results showed that, compared with that of L8, the coefficient of determination (R2) of S2 increased by 26.0%, and the root mean square error (RMSE) and the sum of absolute error (SAE) decreased by 3.0% and 11.4%, respectively. For the ratio vegetation index (RVI) regression model, compared with that of L8, the R2 of S2 increased by 26.0%, and the RMSE and SAE decreased by 8.0% and 20.0%, respectively. When the pixel dichotomy model was used, compared with that of L8, the RMSE of S2 decreased by 21.3%, and the SAE decreased by 26.9%. Overall, S2 performed better than L8 in terms of FVC inversion. Additionally, in this paper, we develop a verified scheme based on UAV data in combination with the object-based classification method. This scheme is feasible and sufficiently robust for building relationships between field data and inversion results from satellite data. Further, the synergy of multi-source sensors (especially UAVs and satellites) is a potential effective way to estimate and evaluate regional ecological environmental parameters (FVC).
- Published
- 2018
12. Signal Molecules Crosstalk and the Critical Role of Jasmonic Acid in Triterpenoid Synthesis Inducement of Aspergillus Niger Elicitor in Suspension Cultured Cyclocarya Paliurus Cells
- Author
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Xiangju Zhou, Chen Jiguang, Meng Wang, Qiong-qiong Xiong, Daobang Tang, Yin Zhongping, Xiaoxiang Xu, and Zhang Qingfeng
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chemistry.chemical_compound ,Crosstalk (biology) ,Paliurus ,chemistry ,Biochemistry ,biology ,Jasmonic acid ,Aspergillus niger ,Triterpenoid synthesis ,Suspension (vehicle) ,biology.organism_classification ,Cyclocarya ,Elicitor - Abstract
Background: Cyclocarya paliurus (C. paliurus) leaves contain multiple health benefical metabolites, and therefore are often used in functional foods and Chinese herbal medicines. However, breeding difficulties confines its utilization. Consequently, cell suspension culture was developed to produce the bioactive secondary metabolites of C. paliurus leaves, but the content was comparatively low. In the present paper, Aspergillus Niger Elicitor (ANE) was used to stimulate the synthesis of triterpenoids in the suspension cultured C. paliurus cells, and the signal molecules crosstalk involved in this elicitation was further studied to interpret the underlying mechanism. Results: Total triterpenoids accumulation of the cultured C. paliurus cells elicited by 200 µg/mL ANE was 9.17 times higher than that of the untreated cells. Nitric oxide (NO), hydrogen peroxide (H2O2) and jasmonic acid (JA) played important roles in the elicitation as signal molecules. Under the ANE stimulation, the concentrations of NO, H2O2 and JA all increased significantly, but presented different change profiles and peaked at different times. Based on series experiments of NO quenching by C-PTIO, H2O2 blocking by DMTU, and JA synthesis inhibition by IBU and NDGA, together with exogenous NO, H2O2 and JA addition experiments, it was deduced that ANE improved triterpenoids synthesis in the suspension cultured C. paliurus cells via a complex signal transduction network, in which three deduced and three hypothetical signal transduction pathways might be involved. JA was not only the junction of NO and H2O2 signal pathways, but also the critical point in the whole signal network. RNA-seq analysis showed that a total of 3 candidate JA synthesis pathway genes including 1 LOX and 2 OPR were found to be significantly up-regulated under the ANE stimulation, along with 5 down-regulated JAZs and 1 up-regulated JAR1 regulating to JA signal transduction.Conclusions: ANE can significantly increase the triterpenoids synthesis in the suspension cultured C. paliurus cells. RNA-seq analysis validated the pivotal role of JA in this ANE elicitation. Our results provided references for the further studies on triterpenoids synthesis in C. paliurus under ANE treatment.
- Published
- 2020
13. Bearing Capacity of Steel Tube Tower Connection under Different Thickness of Gusset Plate
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Kai Niu, Yanzhong Ju, Zhang Qingfeng, Tang Yake, Chen Chen, Haowei Pei, and Liang Zhang
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Materials science ,business.industry ,Steel tube ,Bearing capacity ,Structural engineering ,Gusset plate ,business ,Tower ,Connection (mathematics) - Abstract
In this paper, a finite element model is established to study the influence of connection plate thickness on the bearing capacity of steel tube tower connections. Through the bearing capacity of connections under different connection plate thickness, the influence of connection plate thickness on the bearing capacity of steel pipe tower connections is analyzed. Finally, the relationship between the thickness of connection plates and the bearing capacity of steel tube tower connections is analyzed by regression analysis. The results show that with the increase of the thickness of gusset plate, the bearing capacity of steel tube tower connections increases linearly. The bearing capacity calculated by regression analysis is in good agreement with the finite element simulation results.
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- 2021
14. Insights into genetic variants within sheep IGF2BP1 and their association with litter size
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Cui Mao, Chuanying Pan, Xianyong Lan, Jiang Fugui, Hongfei Liu, Hao Kunjie, Zhang Qingfeng, Han Xufei, Lu Xiaofang, and Haixia Li
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Genetics ,Litter (animal) ,040301 veterinary sciences ,0402 animal and dairy science ,Intron ,food and beverages ,Locus (genetics) ,04 agricultural and veterinary sciences ,Biology ,Fecundity ,040201 dairy & animal science ,0403 veterinary science ,White (mutation) ,Food Animals ,Genotype ,Animal Science and Zoology ,Indel ,Gene - Abstract
Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) plays a crucial role in cellular growth, proliferation, and embryonic development by regulating mRNA stability. IGF2BP1 has been recently found to be located on a new 194.6-kb interval of the fecundity gene FecL. A total of nine insertion/deletion (InDel) variations within IGF2BP1 were identified in 916 adult Australian White sheep, and three were polymorphic: a 5-bp InDel in a downstream region, 9-bp InDel in intron 4, and 15-bp InDel in intron 2. Association analyses indicated that both the 5-bp and 9-bp InDel mutations were significantly associated with litter size at 2nd gestation. The heterozygous genotype (ID) of the 5-bp InDel locus and homozygous insertion genotype (II) of the 9-bp InDel locus were associated with large litter size. Moreover, the combined genotype ID-II of the 5-bp and 9-bp InDel genotypes was identified as the best genotype. These findings will pave the way for future research on marker-assisted selection of reproductive traits in sheep breeding.
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- 2021
15. Estimating Raindrop Kinetic Energy: Evaluation of a Low-Cost Method
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Zhang Qingfeng, Thomas R. Way, Wang Jian, Meng Qinqian, and Dexter B. Watts
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010504 meteorology & atmospheric sciences ,Terminal velocity ,General Engineering ,04 agricultural and veterinary sciences ,Soil surface ,Loess plateau ,Atmospheric sciences ,Kinetic energy ,01 natural sciences ,Intensity (physics) ,Rainfall kinetic energy ,Disdrometer ,040103 agronomy & agriculture ,Erosion ,0401 agriculture, forestry, and fisheries ,Environmental science ,0105 earth and related environmental sciences - Abstract
The Loess Plateau of China is regarded as the most intensively eroded region in the world and soil erosion caused by raindrop impact is a common occurrence on agricultural land within this region. Therefore, understanding the influence of rainfall energy on the soil surface is needed to improve prescriptions for best management practices aimed at mitigating erosion. Disdrometers for measuring rainfall energy are presently available; however, these are relatively expensive and their use may not be justified for determining raindrop energy for predictive soil erosion models in regions where there are limited economic resources. To overcome this constraint, a device was tested for evaluating size and velocity of water drops during rainfall events. This device utilized two rotating disks combined with filter paper to obtain raindrop diameter and velocity which can then be used for determining the kinetic energy of falling raindrops. With this device, raindrop diameter was determined from the resultant raindrop stain left on the filter paper during rainfall events and velocity was calculated from the time it took a falling raindrop to travel between the pair of rotating disks. Measurements were taken for approximately 10 minutes during each of six rainfall events of different intensities over a three month period (from June to August of 2013). The smallest raindrop measured was 0.39 mm diameter and the largest was 5.92 mm diameter. The event average raindrop diameter increased with increasing event rainfall intensity. The minimum raindrop impact velocity was 1.47 m s-1, the maximum was 9.45 m s-1, and the event average terminal velocity increased as event rainfall intensity increased. Estimated raindrop kinetic energy ranged from 0.04 × 10-6 J to 4728.21 × 10-6 J, with event mean raindrop kinetic energy ranging from 40.33 x 10-6 J to 276.94 × 10-6 J. The relationship between estimated event rainfall kinetic energy and event rainfall intensity was represented by an exponential function. The disk device was also compared to an optical disdrometer. The data collected for rainfall intensity, raindrop diameter, and velocity were statistically similar between the two devices. Results from this study show that this low-cost method can be used to estimate rainfall kinetic energy in the Loess Plateau region of Northwest China. Keywords: Loess Plateau, Raindrop diameter, Raindrop velocity, Rainfall intensity.
- Published
- 2017
16. Antibacterial mechanism of the synergistic combination between streptomycin and alcohol extracts from the Chimonanthus salicifolius S. Y. Hu. leaves
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Ning Wang, Lei Cai, Ximei Ye, Xin Liu, Meng Zhao, Xiang Li, Zhang Qingfeng, Jingen Li, Wang Wen-jun, Qi An, Yi Han, and Zitong Zhao
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Staphylococcus aureus ,medicine.drug_class ,Calycanthaceae ,Antibiotics ,Herb-Drug Interactions ,Microbial Sensitivity Tests ,medicine.disease_cause ,Microbiology ,Phosphorus metabolism ,03 medical and health sciences ,0302 clinical medicine ,Drug Discovery ,medicine ,Escherichia coli ,030304 developmental biology ,Pharmacology ,0303 health sciences ,biology ,Chemistry ,Plant Extracts ,Chloramphenicol ,Drug Synergism ,biology.organism_classification ,Anti-Bacterial Agents ,Plant Leaves ,Chimonanthus salicifolius ,Streptomycin ,030220 oncology & carcinogenesis ,Electrophoresis, Polyacrylamide Gel ,Bacteria ,medicine.drug - Abstract
Ethnopharmacological relevance Chimonanthus salicifolius S. Y. Hu. Is a unique traditional medicinal plant in ancient China, and it can eliminate turbid pathogens with aromatics, clear heat, detoxify, prevent colds and influenza, Xinhua Compendium of Materia Medica records that. Aim of the study In previous study, we investigated the regulation of ethanol extracts (EEs) from C. salicifolius S. Y. Hu. leaves on three common antibiotics (chloramphenicol, streptomycin, imipenem) by the checkerboard method. The combination exhibited the best synergy among all combinations, which were composed of streptomycin and 50% EE (SE) from the C. salicifolius S. Y. Hu. leaves. The aim of this study was to investigate the antibacterial mechanism of the SE against Escherichia coli (E. coli, G-) and Staphylococcus aureus (S. aureus, G+). Materials and methods The antibacterial mechanism of the SE was explored by the time-kill test, the phosphorus metabolism, cell membrane integrity assays, the SDS-PAGE, the SEM and TEM observation. Results The time-kill test illustrated that the SE was bacteriostatic with a time-dependent relationship, not sterilization. The phosphorus metabolism indicated that the SE lowered phosphorus consumption. The cell membrane integrity assays demonstrated that the cell membrane was damaged, with the nucleic acid flowing out. The SDS-PAGE analysis found that the SE inhibited the synthesis of the total protein. The SEM and TEM results revealed that the surface and internal ultrastructure of bacteria were damaged. The surface of the bacteria was shriveled and deformed, and the internal structure of the cells was also mutilated. Conclusions The SE damaged the cell membrane, with the cytoplasm flowing out, disturbed the synthesis of total protein and phosphorus metabolism, and ultimately killed the bacteria.
- Published
- 2019
17. Spatial heterogeneity of loess contour tilled microtopographic slope in rainfall erosion
- Author
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Zhang Huihui, Zhang Qingfeng, and Ta Na
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010504 meteorology & atmospheric sciences ,Soil Science ,Soil science ,04 agricultural and veterinary sciences ,Plant Science ,01 natural sciences ,Fractal dimension ,Spatial heterogeneity ,Tillage ,Loess ,040103 agronomy & agriculture ,Erosion ,0401 agriculture, forestry, and fisheries ,Spatial variability ,Variogram ,Soil conservation ,Geology ,0105 earth and related environmental sciences - Abstract
Loess tilled surface is the geographical unit for the quantitative study of the soil erosion process. Contour tillage has been proved to be the most effictive measure for soil and water conservation in the Chinese Loess Plateau. Studies on the spatial heterogeneity of loess tilled surfaces will contribute to the understanding of the mechanism of erosion evolution. For this, a laboratory experiment was performed on contour tilled sloping surfaces where the hydrological-erosive processes were simulated. At different erosion stages, point cloud measurements were made using a terrestrial laser scanning system (TLS); then the heterogeneity depending on detrending and directionality were analysed by both the semivariogram method and the rescaled range analysis method. Results showed that: (1) the fractal dimensions DS and DR were equivalent when determined from either the semivariogram method or the rescaled range analysis method, although the semivariogram method appears to be more reliable in identify...
- Published
- 2016
18. Influence of Surface Crusting on Infiltration of a Loess Plateau Soil
- Author
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Zhang Qingfeng, Dexter B. Watts, Wang Jian, Meng Qinqian, and Thomas R. Way
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Hydrology ,Crust formation ,0208 environmental biotechnology ,Soil Science ,Soil science ,04 agricultural and veterinary sciences ,02 engineering and technology ,Loess plateau ,020801 environmental engineering ,Infiltration (hydrology) ,Soil crust ,Loam ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Precipitation ,Surface runoff - Abstract
Crusting frequently occurs on farmland soil of the Loess Plateau in China and often adversely affects agricultural yields. Therefore, a study was conducted to evaluate the occurrence of soil crusting and its influence on infiltration in a Loess Plateau silt loam soil. Simulated rainfall events were conducted at two intensities (0.67 and 1.33 mm min⁻¹) on four slopes (5, 9, 18, and 29%) under two soil conditions (crusted and uncrusted). Infiltration was evaluated as the difference between precipitation applied and water lost to runoff. A modified Green–Ampt model adjusted to account for soil crusting was also evaluated for predicting infiltration of crusted soil. Mean soil crust thickness was 3.33 and 3.94 mm under rainfall intensities of 0.67 and 1.33 mm min⁻¹, respectively. Slope had no effect on crust formation. In all instances, cumulative infiltration was lower in crusted soil than in uncrusted soil. The time to runoff decreased from 17.98 min in uncrusted soil to 4.64 min in crusted soil under a rainfall intensity of 0.67 mm min⁻¹. Time to runoff also decreased from 16.25 min in uncrusted soil to 4.54 min in crusted soil at a rainfall intensity of 1.33 mm min⁻¹. The modified Green–Ampt model provided a good estimate of soil crusting’s influence on infiltration (coefficient of determination range 0.85–0.97). This suggests that the Green–Ampt model could be used as a tool for predicting soil crusting’s influence on infiltration and runoff from soils of the Loess Plateau.
- Published
- 2016
19. Energy storage locating and sizing method in grid-connected micro-grid
- Author
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Meng Fanbin, Guo Furan, Song Wenzhuo, Gao Yao, and Zhang Qingfeng
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Computer science ,Micro grid ,Grid ,Automotive engineering ,Energy storage ,Sizing - Abstract
In micro grid, the distributed generations have a large proportion and the energy storage system is the fundamental structure of the micro grid. Wind and photovoltaic power generation contain intermittent and uncertain characteristics. Energy storage system in micro grid can smooth the volatility of distributed power and supply power to important loads in case of the insufficiency of distributed power generation. In this paper, a location and capacity planning method of energy storage system is proposed. The energy storage installation points are the key points of the system, which are identified based on the electrical distance. Further, the capacity is optimized and solved on these basics. Finally, the effectiveness of the proposed method is verified through case studies.
- Published
- 2020
20. Application of Compact Type Composite Cross arm in Tower Design
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Chen Chen, Kai Niu, Liang Zhang, Zhang Qingfeng, Fei Zhou, and Haowei Pei
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Materials science ,business.industry ,Composite number ,Structure type ,Structural engineering ,Type (model theory) ,business ,Tower - Published
- 2018
21. Landscape pattern changes and evaluation of ecological service values in a small watershed of the Loess Gully Region
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宋敏敏 Song Minmin, 张青峰 Zhang Qingfeng, 吴秉校 Wu Bingxiao, 吴驳 Wu Bo, and 吴发启 Wu Faqi
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Service (business) ,Landscape pattern ,Watershed ,Geography ,Ecology ,Loess ,Physical geography ,Ecology, Evolution, Behavior and Systematics - Published
- 2018
22. Effect of mevalonic acid on cholesterol synthesis in bovine intramuscular and subcutaneous adipocytes
- Author
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Wan Fachun, Enliang Song, Liu Guifen, You Wei, Cheng Haijian, Zhang Qingfeng, Han Hong, and Liu Xiaomu
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0301 basic medicine ,medicine.medical_specialty ,Subcutaneous Fat ,Gene Expression ,Mevalonic Acid ,Adipose tissue ,Mevalonic acid ,Biology ,Reductase ,03 medical and health sciences ,chemistry.chemical_compound ,Internal medicine ,Adipocyte ,Adipocytes ,Genetics ,medicine ,Animals ,Oil Red O ,Cells, Cultured ,chemistry.chemical_classification ,Cholesterol ,Muscles ,0402 animal and dairy science ,Cell Differentiation ,04 agricultural and veterinary sciences ,General Medicine ,040201 dairy & animal science ,030104 developmental biology ,Endocrinology ,Real-time polymerase chain reaction ,Enzyme ,Adipose Tissue ,chemistry ,Cattle ,Hydroxymethylglutaryl CoA Reductases ,lipids (amino acids, peptides, and proteins) - Abstract
Mevalonic acid (MVA) is a key material in the synthesis of cholesterol; indeed, intracellular cholesterol synthesis is also called the mevalonic acid pathway. 3-Hydroxy-3-methylglutaryl-CoA reductase (HMGR) is an essential enzyme in cholesterol biosynthesis. This study suggests that MVA may play an important role in the differentiation of bovine adipose tissue in vivo. We investigated differential mRNA expression in bovine intramuscular preadipocytes (BIPs) and bovine subcutaneous preadipocytes (BSPs) by culturing cells from the longissimus dorsi muscle and subcutaneous fat tissues of Luxi yellow cattle. The morphology of lipid accumulation of bovine preadipocytes was detected by Oil Red O staining, and total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), and high-density lipoprotein cholesterol (HDLC) levels were measured. Temporospatial expression of HMGR was investigated by real-time quantitative polymerase chain reaction (PCR). The TC, LDLC, and HDLC content did not significantly differ over time but increased slowly with increasing MVA concentration. HMGR expression increased over time and with increasing concentrations of MVA. MVA increased adipose cell proliferation in a dose-dependent and time-dependent manner. MVA stimulated HMGR expression in two cell types and its influence on adipocyte differentiation.
- Published
- 2015
23. Capacitor-Loaded Spoof Surface Plasmon (SSP) for Flexible Dispersion Control and High-Selectivity Filtering
- Author
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Tang, Xiaolan, Zhang, Qingfeng, Hu, Sanming, Kandwal, Abhishek, Guo, Tongfeng, and Chen, Yifan
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Classical Physics (physics.class-ph) ,FOS: Physical sciences ,Physics - Classical Physics ,Physics - Optics ,Optics (physics.optics) - Abstract
This letter proposes a new spoof surface plasmon transmission line (SSP-TL) using capacitor loading techniques. This new SSP-TL features flexible and reconfigurable dispersion control and highly selective filtering performance without resorting to configuration change. Moreover, it requires much smaller line width than the conventional SSP-TLs for achieving a extremely slow wave (or a highly confined field), which is quite useful for a compact system. To illustrate the design principle, several examples are designed within the frequency range of 2-8 GHz. Both numerical and experimental results are given in comparison with the conventional SSP-TL. It is demonstrated that the proposed technique provides a better performance in size reduction and dispersion reconfigurability.
- Published
- 2017
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24. Synthesis of Negative Group Delay Using Lossy Coupling Matrix
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Das, Ranjan and Zhang, Qingfeng
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FOS: Physical sciences ,Physics - Applied Physics ,Applied Physics (physics.app-ph) - Abstract
In this paper, a systematic synthesis approach is proposed for achieving negative group delay responses using lossy coupling matrix. It is mathematically proved that, for a passive and reciprocal network, loss is the necessary condition to realize a negative group delay. Also, the optimum strategy is to place zeros and poles of the transfer function both on the left complex plane. A closed-form relation between the group delay and magnitude is then derived based on this strategy, and followed by a complete synthesis approach using coupling matrix. Two numerical and one experimental examples are finally given to illustrate the proposed synthesis method.
- Published
- 2017
- Full Text
- View/download PDF
25. Astrometric reduction of Cassini ISS images of Helene
- Author
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Meng Xiao-hua, Xiong YuTao, Li Zhan, Wang Na, Zhang Qingfeng, and Peng Qing-yu
- Subjects
Physics ,Position (vector) ,Rings of Saturn ,International Celestial Reference Frame ,Satellite ,Astrometry ,Right ascension ,Ephemeris ,Geodesy ,Declination - Abstract
Helene is a small irregular Saturnian satellite. It is difficult to observe Helene by ground-based telescopes because of its weak lightness (18.5 mag) and proximity to Saturns rings. The number of historical observations of the satellite is small, but a large number of images of Helene were obtained between 2004 and 2017 using the Imaging Science Subsystem (ISS) in Cassini Spacecraft. In this paper, astrometry reduction was performed based on these observations. Specifically, we first corrected the initial pointing of the Narrow Angle Camera in ISS using the referencing Gaia DR2, and then measured the Helenes center position in image coordinates using the two-dimensional Gaussian fitting method. Finally the position was transformed to the Right Ascension ($\alpha$) and Declination ($\delta$) in International Celestial Reference Frame (ICRF) centered at Cassini. The result was compared with JPL SAT393 ephemerides, and the position residual was calculated. Totally 890 images were effectively measured. The results showed that compared with SAT393, the mean values of all residuals in $\alpha$$*$cos$(\delta)$ and $\delta$ directions were $0.23$ and $-0.63$ km, respectively, and the standard deviations were $3.48$ and $2.23$ km, respectively. This precision was much higher than that of ground observations, indicating the advantage of space-based observations.
- Published
- 2018
26. Vegetation landscape pattern change and characteristics of spatial distribution in south edge of Mu Us Sandy Land
- Author
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周淑琴 Zhou Shuqin, 张青峰 Zhang Qingfeng, 荆耀栋 Jing Yaodong, and 吴发启 Wu Faqi
- Subjects
Landscape pattern ,Ecology ,Primary producers ,media_common.quotation_subject ,Spatial distribution ,Evenness index ,Desertification ,Dominance (ecology) ,Environmental science ,Species evenness ,Turning point ,Physical geography ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
The south edge of Mu Us sandy land belongs to the Erdos Plateau and the Loess Plateau transition zone.At the same time the area is the typical farming-pastoral region and the ecological environment is extremely fragile.Vegetation as the primary producers of ecological system not only provides the system required organic substances and biological chemical energy,but also can improve and adjust the environment in the ecological systems.Vegetation change is the most intuitive performance of desertification development or reversal.It also is the sensitive index of the climate and human factors impacting on the ecological environment.Vegetation pattern information of Dingbian County can be served as vegetation protection,restoration and reconstruction. Remote-sensing data includes the TM or ETM+ images of 1991,1999 and 2007 in this study.Vegetation coverage information extracted from 1991 to 207 by using RS and GIS is divided into two areas according to different landform.Landscape indexes of two zones calculated are used to analysis vegetation pattern changes.The results show the following conclusions.(1)The turning point of vegetation coverage is 1991 in two zones during sixteen years.Vegetation coverage conditions continue to worsen in the first stage while both improve in the second stage.The lower and low level accounted for the absolute superiority.Meanwhile,both levels in two zones is increasing from 1991 to 1999.It has risen from 55% to 70% in sandy areas and from 70% to 80% in hilly region.The high level ratio below 5% is continuing to decline.In two zones dominance level are changed to low and moderate level in 2007.They are 55% in sandy area,70% in hilly region.The high level has risen with different degree.(2)After 1999 the vegetation landscape pattern changes reversed.Landscape pattern change trend is the same but the degree is different.Landscape diversity and landscape evenness firstly decreases and then increases.Types of alternating distribution firstly wake and then enhances.The landscape fragmentation index of sandy areas firstly increases and then decreases,while continuously rising in hilly region.On the whole sandy areas landscape fragment degree is small and diversity is high.Vegetation alternating distribution is obvious and evenness index is high.The characteristic of landscape pattern is on the contrary in hilly region.The interference from outside is strong in sandy area,but weak in hilly region.(3)Vegetation pattern is the multi-core model during evolvement process.Meanwhile,the core size,shape and type change in different degrees.Sandy area core mostly is non-vegetation patches while hilly area high vegetation coverage level patches.Vegetation around the core distribution shows a gradient.
- Published
- 2013
27. Directional flow rate determination in trunks of apple trees in China’s Loess Mountain
- Author
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孟秦倩 Meng Qinqian, 吴发启 Wu Faqi, 张青峰 Zhang Qingfeng, and 王健 Wang Jian
- Subjects
Hydrology ,Ecology ,Agroforestry ,Loess ,China ,Ecology, Evolution, Behavior and Systematics ,Geology ,Volumetric flow rate - Published
- 2013
28. Eco-economic regionalization of the Loess Plateau
- Author
-
Zhang QingFeng and Wu FaQi
- Subjects
Geography ,Ecology ,Soil Science ,Soil science ,Plant Science ,Physical geography ,Loess plateau ,Agronomy and Crop Science ,Ecology, Evolution, Behavior and Systematics - Published
- 2009
29. Comparing Method Analysis for Lower Steam Temperature of 660MW Supercritical Lignitic Boiler
- Author
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Zhang Qingfeng, Li Yuanyuan, Li Jinjing, and Zhao Zhenning
- Subjects
Flash boiler ,Steam drum ,Waste management ,Petroleum engineering ,Superheated steam ,Steam temperature ,Boiler (power generation) ,Boiler feedwater ,Environmental science ,Feedwater heater ,Supercritical fluid - Published
- 2015
30. Single-Step Tunable Group Delay Phaser for Real-Time Spectrum Sniffing
- Author
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Guo, Tongfeng, Zhang, Qingfeng, Chen, Yifan, Wang, Rui, and Caloz, Christophe
- Subjects
FOS: Physical sciences ,Physics - Optics ,Optics (physics.optics) - Abstract
This paper presents a single-step tunable group delay phaser for spectrum sniffing. This device may be seen as a "time filter", where frequencies are suppressed by time separation rather than by spectral attenuation. Compared to its multiple-step counterpart, this phaser features higher processing resolution, greater simplicity, lower loss and better channel equalization, due to the smaller and channel-independent group delay swing. A three-channel example is provided for illustration.
- Published
- 2015
- Full Text
- View/download PDF
31. Compact Reflection-Type Phaser Using Quarter-Wavelength Transmission Line Resonators
- Author
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Liao, Weiwei, Zhang, Qingfeng, Chen, Yifan, and Caloz, Christophe
- Subjects
Classical Physics (physics.class-ph) ,FOS: Physical sciences ,Physics - Classical Physics ,Physics - Optics ,Optics (physics.optics) - Abstract
A compact reflection-type phaser composed of quarter-wavelength transmission line resonators interconnected by alternating K- and J-inverters is proposed. A design method is also presented. To validate this method, a 4th-order example is designed and fabricated. The proposed phaser is shown to exhibit the benefits of smaller size, easier fabrication and suppressed even-order harmonics compared with previously reported half-wavelength phasers.
- Published
- 2014
- Full Text
- View/download PDF
32. Planar Reflective Phaser and Synthesis for Radio Analog Signal Processing (R-ASP)
- Author
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Zou, Lianfeng, Zhang, Qingfeng, and Caloz, Christophe
- Subjects
FOS: Physical sciences ,Physics - Optics ,Optics (physics.optics) - Abstract
A planar reflective phaser based on an open-ended edge-coupled-line structure is proposed. This phaser is the first reported phaser that combines the benefits of high resolution, inherent to cross-coupled resonator reflective phasers, and of compactness, inherent to planar circuits. A 4-ns swing 4.9-5.5 GHz quadratic phase (linear group delay) 4th-order microstrip phaser is synthesized and experimentally demonstrated. Given its advantages, this phaser may find vast applications in Radio Analog Signal Processing (R-ASP) systems., Comment: 2 pages, 4 figures
- Published
- 2014
- Full Text
- View/download PDF
33. Study on the Gearbox's Time-Variation Dynamics Model in Angular Domain
- Author
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Zhang Qingfeng, Cui Xiu-mei, and Hou Cai-hong
- Subjects
Engineering ,Steady state ,Relation (database) ,business.industry ,Dynamics (mechanics) ,Mathematical analysis ,Mechanical engineering ,Variation (game tree) ,Time domain ,Physics::Classical Physics ,business ,Domain (software engineering) - Abstract
Aiming at the relation of gearbox's parameters and rotating angle, this paper puts forward the gearbox's dynamics Model in Angular Domain, and the parameter conversion from time Domain to Angular Domain can be achieved, by this means, Unsteady-State in time Domain will convert into Steady State in Angular Domain, it will play an important role in analyzing gearbox's Unsteady-State characteristics.
- Published
- 2013
34. Study on the characteristics of gas jet for engine using high speed photography
- Author
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Dong Yuebo, Li Dan, Geng Duan-yang, and Zhang Qingfeng
- Subjects
Physics ,Jet (fluid) ,Jet velocity ,Optics ,business.industry ,Astrophysics::High Energy Astrophysical Phenomena ,High-speed photography ,High Energy Physics::Experiment ,Rotational speed ,Penetration (firestop) ,Mechanics ,business ,Two stages - Abstract
A study on the movement of the gas jet is shot in real-time by the high speed photography and disposes the images with the professional software Image-Pro6.3. The author selects the vertex of the gas jet as a subject investigated to research the variation of the jet penetration, the jet dispersion angle and the jet velocity along with the jet time according to the theory of the free jet. The results show that: the gas jet development process is divided into two stages: the initial section and the main section. When the rotational speed of the engine is a definite value along with the jet time, the jet penetration increases, the jet dispersion angle remains unchanged and the jet velocity decreases. When the rotational speed increases, the jet penetration and jet velocity reduce, but the jet dispersion angle raises, then determines the mathematical model between the jet velocity and the jet penetration on this basis.
- Published
- 2011
35. Detection of Gear Fault Based on Amplitude Demodulation of Rotary Speed
- Author
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Cui Xiu-mei, Tang Liwei, Hou Cai-hong, and Zhang Qingfeng
- Subjects
Vibration ,Amplitude modulation ,Signal processing ,Torsional vibration ,Noise (signal processing) ,Computer science ,Acoustics ,Demodulation ,Time domain ,Fault (power engineering) - Abstract
Aiming at the features of the engaging vibration’s direct effects on the rotary speed of axis, this paper puts forward the faults diagnosis method of gearbox using amplitude demodulation technology to analyze the signals of rotary speed. First, the signals of rotary speed of gearbox are synchronously sampled in time domain; Next, the signals of torsional vibration are worked out using the signals of rotary speed, and the signals are averaged in time domain to decrease the noise and increase the power signal-to-noise ratio; Last, the averaged signals in time domain are analized with amplitude demodulation and according to the function graph of the amplitude demodulation, the features of the gear fault are picked up. With the analysis of the fault experimental signals of partially abraded gears, partially abraded faults are effectively diagnosed with this method.
- Published
- 2010
36. Rural biomass energy 2020: People's Republic of China
- Author
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Zhang, Qingfeng, Watanabe, Makiko, and Lin, Tun
- Subjects
jel:O13 ,jel:Q42 ,rural biomass energy ,rural development ,biomass resources ,biomass technologies ,China ,jel:O1 ,jel:Q4 - Abstract
The developing world is looking for effective, creative ideas for upscaling clean, renewable energy. No place will gain more socially, economically, and environmentally from increased access to clean, reliable energy than poor, rural areas. Biomass energy, produced from animal and crop wastes, is a sensible renewable energy option for rural areas and it can be cost-effective at community and industry scales if guided effectively by governments. This publication explores the potential of biomass energy to close the urban–rural energy gap, raise farmer incomes, and mend the environment in the People’s Republic of China (PRC). Its findings are instructive for other developing and medium-income countries exploring energy-for-all strategies. The report examines the promises and limitations of leading biomass energy technologies and resources for various distribution scales, including but not limited to household biogas digesters. The information is based on lessons learned and experiences from the Asian Development Bank–financed Efficient Utilization of Agricultural Wastes Project in the PRC, as well as findings and conclusions from a technical assistance grant to assist the government draft a national strategy for developing rural biomass energy.
- Published
- 2010
37. Develop A New Type Apparatus for Measuring Inner Diameter of Gun Barrel Using Optical Grating Sensor
- Author
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Wang Wei, Zhang Qingfeng, and Tang Liwei
- Subjects
Materials science ,Optics ,Diameter measurement ,business.industry ,Physics::Optics ,Inner diameter ,business ,Diffraction grating ,Gun barrel - Abstract
In aimed at the technic actuality of measuring inner diameter of gun barrel, we set forth a technique for improving precision of measuring inner diameter of gun barrel. The optical grating measuring apparatus developed has overcome the limitation of traditional optical grating measuring apparatus, and has resolved the puzzle of inaccurate count for traditional optical grating measuring apparatus. The results show that measuring technique using optical grating sensor has extensive application foreground.
- Published
- 2007
38. Backward-to-Forward Wide-Angle Fast Beam-Scanning Leaky-Wave Antenna With Consistent Gain
- Author
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Yang Yang, Gaofeng Wang, Peng Zhao, Debabrata K. Karmokar, Qingfeng Zhang, Liang Peng, Shichang Chen, Kuiwen Xu, Hao Jiang, Jiang, Hao, Xu, Kuiwen, Zhang, Qingfeng, Yang, Yang, Karmokar, Debabrata K, Chen, Shichang, Zhao, Peng, Wang, Gaofeng, and Peng, Liang
- Subjects
Capacitive coupling ,consistent gain ,Materials science ,broadside radiation ,business.industry ,Frequency band ,Leaky wave antenna ,Impedance matching ,LWA ,020206 networking & telecommunications ,02 engineering and technology ,Stopband ,continuous beamscanning ,Microstrip ,OSB ,Microstrip antenna ,Optics ,0906 Electrical and Electronic Engineering, 1005 Communications Technologies ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,Antenna (radio) ,leaky-wave antenna ,Networking & Telecommunications ,business ,open stopband - Abstract
A planar periodic leaky-wave antenna (PLWA) with continuous backward-to-forward beam-scanning capability and consistent gain is presented. The PLWA is made of a new type of periodically arranging meander line structures, in which the capacitive coupling between neighboring units plays the key role in achieving a high scanning rate. In detail, the beam-scanning rate of the proposed PLWA is efficiently tuned by varying the gap between two adjacent units, without considerably changing the working frequency band. To mitigate the open stopband (OSB) and to improve the impedance matching, several inductive open stubs are introduced into a single meander line unit cell to enhance the radiation. In the experiment, a prototype of the proposed PLWA was fabricated and measured. The simulated and measured beams show good agreement in terms of scanning range and radiation performance. A continuous beam scanning from −60° to +58° through broadside in the frequency band of 5.95–7.1 GHz is observed, and hence, a 102.6°/GHz scanning rate is realized in practice. Besides, the PLWA shows an average gain level of 11.96 dBi with a variation lower than 2 dB and a sidelobe below −10 dB at all the measured frequencies. The proposed PLWA may have potential applications in radar, microwave imaging, and wireless communication due to its compact structure, easy to fabricate, and dispersionless performance. Refereed/Peer-reviewed
- Published
- 2021
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