|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Interactive effects of wind speed,vegetation coverage and soil moisture in controlling wind erosion in a temperate desert steppe,Inner Mongolia of China显示文摘The rapid desertification of grasslands in Inner Mongolia of China poses a significant ecological threaten to northern China. The combined effects of anthropogenic disturbances(e.g., overgrazing) and biophysical processes(e.g., soil erosion) have led to vegetation degradation and the consequent acceleration of regional desertification. Thus, mitigating the accelerated wind erosion, a cause and effect of grassland desertification, is critical for the sustainable management of grasslands. Here, a combination of mobile wind tunnel experiments and wind erosion model was used to explore the effects of different levels of vegetation coverage, soil moisture and wind speed on wind erosion at different positions of a slope inside an enclosed desert steppe in the Xilamuren grassland of Inner Mongolia. The results indicated a significant spatial difference in wind erosion intensities depending on the vegetation coverage, with a strong decreasing trend from the top to the base of the slope. Increasing vegetation coverage resulted in a rapid decrease in wind erosion as explained by a power function correlation. Vegetation coverage was found to be a dominant control on wind erosion by increasing the surface roughness and by lowering the threshold wind velocity for erosion. The critical vegetation coverage required for effectively controlling wind erosion was found to be higher than 60%. Further, the wind erosion rates were negatively correlated with surface soil moisture and the mass flux in aeolian sand transport increased with increasing wind speed. We developed a mathematical model of wind erosion based on the results of an orthogonal array design. The results from the model simulation indicated that the standardized regression coefficients of the main effects of the three factors(vegetation coverage, soil moisture and wind speed) on the mass flux in aeolian sand transport were in the following order: wind speed>vegetation coverage>soil moisture. These three factors had different levels of interactive effects on the mass flux in aeolian sand transport. Our results will improve the understanding of the interactive effects of wind speed, vegetation coverage and soil moisture in controlling wind erosion in desert steppes, and will be helpful for the design of desertification control programs in future. | MENG Zhongju DANG Xiaohong GAO Yong REN Xiaomeng DING Yanlong WANG Meng | 2018 | Journal of Arid Land2018，10，4： | 19 |
| 2 | Bolt-grouting combined support technology in deep soft rock roadway显示文摘Analyzing the mineral composition, mechanical properties and ground stress testing in surrounding rock,the study investigated the failure mechanism of deep soft rock roadway with high stress. The boltgrouting combined support system was proposed to prevent such failures. By means of FLAC3D numerical simulation and similar material simulation, the feasibility of the support design and the effectiveness of support parameters were discussed. According to the monitoring the surface and deep displacement in surrounding rock as well as bolt axial load, this paper analyzed the deformation of surrounding rock and the stress condition of the support structure. The monitor results were used to optimize the proposed support scheme. The results of field monitors demonstrate that the bolt-grouting combined support technology could improve the surround rock strength and bearing capacity of support structure, which controlled the great deformation failure and rheological property effectively in deep soft rock roadway with high stress. As a result, the long term stability and safety are guaranteed. | Chen Yanlong Meng Qingbin Xu Guang Wu Haoshuai Zhang Guimin | 2016 | International Journal of Mining Science and Technology2016，26，5： | 10 |
| 3 | Influence of dynamic pressure on deep underground soft rock roadway support and its application显示文摘Due to high ground stress and mining disturbance, the deformation and failure of deep soft rock roadway is serious, and invalidation of the anchor net-anchor cable supporting structure occurs. The failure characteristics of roadways revealed with the help of the ground pressure monitoring. Theoretical analysis was adopted to analyze the influence of mining disturbance on stress distribution in surrounding rock,and the change of stress was also calculated. Considering the change of stress in surrounding rock of bottom extraction roadway, the displacement, plastic zone and distribution law of principal stress difference under different support schemes were studied by means of FLAC3D. The supporting scheme of U-shaped steel was proposed for bottom extraction roadway that underwent mining disturbance. We carried out a similarity model test to verify the effect of support in dynamic pressure. Monitoring results demonstrated the change rules of deformation and stress of surrounding rock in different supporting schemes. The supporting scheme of U-shaped steel had an effective control on deformation of surrounding rock. The scheme was successfully applied in underground engineering practice, and achieved good technical and economic benefits. | Meng Qingbin Han Lijun Chen Yanlong Fan Jiadong Wen Shengyong Yu Liyuan Li Hao | 2016 | International Journal of Mining Science and Technology2016，26，5： | 4 |
| 4 | The analysis of electrical performances of nanowires silicon solar cells显示文摘A theoretical model of silicon solar cells with ultra-small textured surface has been established based on depletion approximation and drift diffusion theory. The ultra-small textured surface achieves the low reflectance by multiple reflections among the silicon nanowires(NWs) . The electrical performances of the solar cells,including open circuit voltage(Voc),short circuit current(Isc) and conversion efficiency(η),are analyzed by the theoretical model. The results show that the low reflectance is not the only pursuit in manufacturing the Si NWs solar cells. Other factors including optimizing the surface passivation,improving the silicon wafers quality and designing the proper nanowire length should be considered together with NWs structure. | LI HaoFeng JIA Rui DING WuChang CHEN Chen MENG YanLong LIU XinYu | 2011 | Science China(Technological Sciences)2011，54，12： | 4 |
| 5 | Age assignment and geological significance of the “Budate Group” in the Hailar Basin显示文摘Age and nature of the Budate Group in the Hailar Basin are of great significance in studying the evolution of the Hailar Basin and the Xing'an-Mongolian Orogenic Belt(XMOB).Zircon U-Pb ages of eight volcanic rocks from the Budate Group and two basement granites in the Hailar Basin were reported in this study.The dating results indicated that the formation of these volcanic rocks was consistent with the emplacement of Late Paleozoic basement granite in age(356-290 Ma),i.e.,Early Carboniferous to Early Permian rather than Early Mesozoic.Combined with regional geology,it was concluded that the Budate Group is the component of the basement of the Hailar Basin,and these volcanic rocks were formed at an active continental margin,which is related to the closure of the Hegen Mountains suture zone.The captured Neoproterozoic zircons(814-873 Ma) were probably derived from the Neoproterozoic basement materials in the Ergun Block,implying the close genetic relationships between the Ergun Block(including the Hailar Basin) and the Siberian Block. | MENG Qi'An WAN ChuanBiao ZHU DeFeng ZHANG YanLong GE WenChun WU FuYuan | 2013 | Science China Earth Sciences2013，56，6： | 4 |
| 6 | Research on ultra-small textured surface of multicrystalline silicon solar cell显示文摘The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface protection method and front surface passivation method have been used in the multicrystalline solar cells with ultra-small textured surfaces.With these improvements,the back surface remains intact after the etch process and the efficient minority lifetime is apparently increased.The test result shows that the solar cell with ultra-small textured surface can obtain better electrical performances by these improvements. | LI HaoFeng JIA Rui DOU BingFei CHEN Chen XING Zhao YANG YongZhou DING WuChang MENG YanLong LIU XinYu YE TianChun LI ShangQing | 2013 | Science China(Technological Sciences)2013，56，4： | 2 |
| 7 | Effects of wind guide plates on wind velocity acceleration and dune leveling: a case study in Ulan Buh Desert, China显示文摘The areas used to be covered by shifting sand dunes have been reclaimed rapidly in recent years. However, it is a challenge to reclaim high sand dunes because it is rather costly to level the high dunes to gentle arable lands. In this study, a wind guide plate was used to change the characteristics of natural wind to level the sand dunes. The use of wind energy could significantly increase the efficiency of dune leveling and decrease the cost. Low wind velocity is a typical characteristic in Ulan Buh Desert of China where the average wind speed is much lower than the threshold velocity for sand movement. The experiment of this study was conducted to accelerate the wind velocity by a wind guide plate to level a sand dune. Results show that the threshold velocity for sand movement is 3.32 m/s at 10 cm above the sand surface in Ulan Buh Desert. A wind guide plate set at an angle less than 50° could significantly increase the wind velocity. The wind velocity could be accelerated up to the threshold velocity for sand movement behind a plate when the plate is at the angles of 20°, 25°, 35° and 40°. The most significant acceleration of wind velocity appears at 1.5 and 3.0 m behind the plate with an angle of 25°. An obvious wind velocity acceleration zone exists behind the wind guide plate when the angles are at 25°, 35°, 40° and 45°, with the most obvious zone under the angle of 45°. The results also show that the total amount of sand transferred over the experimental period increased by 6.1% under the effects of wind guide plates compared to the sand moved without wind guide plates. The results of the study will provide theoretical and practical supports for desert management in sand dune areas. | HAN Yanlong GAO Yong MENG Zhongju DANG Xiaohong JIA Xu DING Yanlong LI Peng | 2017 | Journal of Arid Land2017，9，5： | 2 |
| 8 | Very low turn-on voltage and high brightness tris-(8-hydroxyquino- line) aluminum-based organic light-emitting diodes with a MoOx p-doping layer显示文摘 | Xie Guohua Meng Yanlong Wu Fengmin | 2008 | Applied Physics Letters2008，92，9： | 1 |
| 9 | Woodchuck hepatitis post-transcriptional regulatory element improves transgene expression and stability mediated by episomal vectors in CHO-K1 cells显示文摘Gene therapy is an effective strategy for treating several diseases,and safe and efficient vector systems are the basis for gene therapy applications.The non-viral episomal vectors are preferred as a gene transfer tool because they do not integrate into the host cell chromosome,which can avoid insertion mutation to prevent host immune response and potential tumorigenicity during disease treatment.In our previous study,we constructed an episomal vector driven by human cytomegalovirus major immediate-early(CMV)promoter and mediated by the characteristic motifs of scaffold/matrix attachment regions(S/MARs)[1].The vector contains only 387-bp MARs instead of the 2200-bp S/MARs in the original non-viral episomal vector pEPI,which showed the higher transgene efficiency and expression level[2]. | Xiaoyin Wang Weili Zhang Yanlong Jia Meng Wang Dandan Yi Tian-yun Wang | 2020 | Acta Biochimica et Biophysica Sinica2020，52，11： | 1 |
| 10 | Research on the surface passivation of nanostructure-textured crystalline silicon solar cell显示文摘Nanostructure-textured solar cell owns unique properties but has some shortages especially in its fabrication and passivation.In this paper,nanostructures for crystalline silicon solar cell have been synthesized by controllable method based on silver catalyzed chemical etching.In this way,only the front surface of cell is etched and rear surface is protected.It was found that cells textured via the new method obtained equally excellent optical while superior electrical properties compared with those textured via traditional HF/AgNO3 etching.The V OC and I SC of the cell were improved by 6% and 11%,respectively.Then the cells were passivated via a bi-layer passivation(SiO2 & SiN x),in contrast to traditional SiN x passivation.It was also found that cells with new passivation exhibited improved V OC and I SC by 4% and 25%,respectively.The encouraging results can provide fundamental data for developing the nanostructure-textured crystalline silicon solar cell in following researches. | DOU BingFei JIA Rui LI HaoFeng CHEN Chen MENG YanLong LIU XinYu YE TianChun | 2013 | Science China(Technological Sciences)2013，56，1： | 0 |
| 11 | Primary central nervous system lymphoblastic B cell lymphoma located at cerebellum in a child: A case report and literature review显示文摘Introduction:Primary central nervous system lymphoma(PCNSL)is extremely rare in pediatric population.We reported a case of PCNSL in a 3-year-old girl and reviewed the literature in the past three decades.Case presentation:A 3-year-old girl presented with gait disturbance.A contrast-enhanced magnetic resonance image of the brain showed a solitary bulky mass in the left cerebellar hemisphere,hydrocephalus and cerebellar tonsillar hernia.Surgical resection was performed and the patient was diagnosed with primary central nervous system lymphoblastic B cell lymphoma.Then the patient received regular chemotherapy,including 6 cycles of chemotherapy containing high-dose methotrexate(HD-MTX).The patient remains alive 15 months after the diagnosis with no evidence of active disease,but suffered twice chronic subdural hematoma,which was treated by burr hole drainage.Conclusion:Lymphoblastic B cell lymphoma is a rare histologic subtype of pediatric PCNSL.Chemotherapy containing HD-MTX remains the most effective treatment.The patient should avoid head impact after surgical resection of the tumor to prevent chronic subdural hematoma. | Xueliang Yang Yanlong Duan Chunju Zhou Ling Jin Ningning Zhang Shuang Huang Meng Zhang Jing Yang Yonghong Zhang | 2021 | Pediatric Investigation2021，5，4： | 0 |
| 12 | Experimental study on sand production and coupling response of silty hydrate reservoir with different contents of fine clay during depressurization显示文摘To further understand the characteristics of clay and sand production(hereafter collectively referred to as sand production)and to provide optimization designs of sand control schemes are critical for gas production from clayey silt natural gas hydrate reservoirs in the South China Sea.Thus,gas-water-sand production behavoirs and coupling reservoir subsidence characteristics before,during,and after hydrate dissociation of the clayey silt hydrate reservoirs with different clay contents(5%,10%,15%,20%,25%,and 30%)have been studied through a self-developed experimental system.The results show that with the increase of clay content,the total mass of sand production first increases and then decreases,and it reaches maximum when the clayey content is 20%.The sand production is the lowest before hydrate dissociation and increases significantly during hydrate dissociation,which mainly occurs in the high-speed gas and water production stage at the beginning of hydrate dissociation.After hydrate dissociation,the sand production decreases significantly.During the whole depressurization process,the clay and free sand particles generally move to the sand outlet due to the fluid driving force and overlying stress extrusion.However,for conditions of high clay contents,those particles fail to pass through the sand control screen and gradually accumulate and block the screen by forming a mud cake,which greatly reduce the permeability of the screen and limite sand production as well as gas and water production.Our research lays a foundation for sand production prediction and sand control scheme selection during gas recovery from clayey silty hydrate reservoirs that greatly need to consider a balance between sand control and gas productivity. | Xiangyu Fang Dianheng Yang Fulong Ning Linjie Wang Zhichao Liu Yanjiang Yu Wenwei Xie Hongfeng Lu Yanlong Li Meng Xu | 2023 | Petroleum2023，9，1： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员