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Evaluation on Killing Effects of Sensitive Plant Growth Inhibitors on Eupatorium adenophorum 被引量:1
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作者 戴红燕 华劲松 《Agricultural Science & Technology》 CAS 2014年第1期79-82,共4页
[Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. ... [Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. [Method] According to field test method, the effects of treatments with growth inhibitor at 0.5%, 1%, 1.5%and 2% on Eupatorium adenophorum were explored and the growth of other weeds was observed to research selectivity of plant inhibitor on the plant. [Result] The growth inhibitor had significant effects on ground parts of Eupatorium adenophorum. Specifical y, after 2 h, Eupatorium adenophorum was damaged seriously and the damage degree went worse upon inhibitor concentration. After 5 d, the control effect of the inhibitorreached 41.5% with concentration at 1.5%, reached 90.2% with the concentration at 1%, and 100% with the concentration at 1.5% and 2%. After 15 d, the control effect achieved 64.6%, 91.7%, 98.9% and 100% with concentrations at 0.5%, 1%, 1.5% and 2%. Stil , the effects of growth inhibitors on root system were limited. For example, new branches would grow from base part if the inhibitor con-centration is too low. On the other hand, the growth inhibitor is of sensitivity and selectivity, which would not hurt other plants. [Conclusion] It is feasible to rapidly control growth and development and even kil Eupatorium adenophorum based on plant sensitivity and it is proved that the growth inhibitor at 1.5% would considerably restrict and kil Eupatorium adenophorum. Therefore, the concentration of growth in-hibitors should be over 1.5%. 展开更多
关键词 Eupatorium adenophorum sensitivity Growth inhibitor Control effects
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A semi-analytical model for coupled flow in stress-sensitive multi-scale shale reservoirs with fractal characteristics 被引量:2
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作者 Qian Zhang Wen-Dong Wang +4 位作者 Yu-Liang Su Wei Chen Zheng-Dong Lei Lei Li Yong-Mao Hao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期327-342,共16页
A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes... A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation. 展开更多
关键词 Multi-scale coupled flow Stress sensitivity Shale oil Micro-scale effect Fractal theory
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Influence of pre-stretching on quench sensitive effect of high-strength Al-Zn-Mg-Cu-Zr alloy sheet 被引量:9
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作者 HE Ke-zhun LI Qun +2 位作者 LIU Sheng-dan ZHANG Xin-ming ZHOU Ke-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第9期2660-2669,共10页
The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and different... The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and differential scanning calorimetry(DSC).The water-cooled and aged alloy exhibits higher strength than the air-cooled and aged alloy;2.5%pre-stretching of tensile deformation exerts little effect on strength of water-cooled and aged alloy but increases that of air-cooled and aged one,and therefore the yield strength reduction rate due to slow quenching decreases from about 3.8%to about 1.0%,reducing quench sensitive effect.For the air-cooled alloy,pre-stretching increases the sizes ofη'strengthening precipitates but also increases their quantity and the ratio of diameter to thickness,resulting in enhanced strengthening and higher strength after aging.The reason has been discussed based on microstructure examination by TEM and DSC. 展开更多
关键词 high-strength aluminum alloy PRE-STRETCHING tensile properties quench sensitive effect strengthening precipitates
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Preoperative diagnosis and operative effect of intracranial aneurysm with three-dimensional computed tomography angiography 被引量:11
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作者 Xuxin Zhang Junhong Guan Duo Chen Yongjie Yang Xiangtai Wei 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期358-360,共3页
BACKGROUND : Digital subtraction angiography (DSA) is always regarded as the golden standard for diagnosis of intracranial aneurysm; however, the procedure is complex, traumatic, expensive and easy to induce vascul... BACKGROUND : Digital subtraction angiography (DSA) is always regarded as the golden standard for diagnosis of intracranial aneurysm; however, the procedure is complex, traumatic, expensive and easy to induce vascular complication. Three-dimensional computed tomography angiography (3D-CTA) can make up deficiencies of DSA; therefore, it is used in clinical therapy wider and wider. OBJECTIVE : To evaluate the clinical effect of 3D-CTA on disruption and hemorrhage of intracranial aneurysm pre- and post-operation and compare with the effect of DSA. DESIGN : Auto-control contrast observation SETTING : Department of Neurosurgery, Shengjing Hospital of China Medical University PARTICIPANTS : A number of 106 patients with disruption and hemorrhage of intracranial aneurysm were selected from the Department of Neurosurgery, Shengjing Hospital of China Medical University from January 2003 to April 2006. All patients were diagnosed with cranial operation and consent. There were 47 males and 59 females aged from 3-76 years with the mean age of (47±13) years. Among them, 82 patients had extensive subarachnoid hemorrhage (SAH), 7 had hemorrhage at longitudinal fissure, and 17 had hemorrhage at ambiens cistema and lateral fissure. Moreover, intraventricular hematocele was accompanied on 13 patients and hematom on 9 patients. METHODS: (1) 3D-CTA examination: Siemens SOMATOM Sensation 64 CT was used in this study. The thickness was 1 mm and interval of reconstruction was 0.8 mm. Localizing section was plainly scanned as the standard of canthus line. Scan ranged from 30 mm below sella to 50 mm above sella. Non-ion contrast medium of Omnipaque 350 (concentration of iodine was 350 g/L) was inserted into anterior vein of elbow with 18G trochar retained with high-pressured injectoc pum. The speed was 4.5 mL/s and the total volume was 80-100 mL with the means of 90 mL. Scan started at 10-20 s after injection of contrast medium. Original image was dealt with Leonardo workstation and retreated with Syngo software. Volume rendering and maximum intensity projection were used to reconstructed images, (2) All 106 patients suffered from occlusion of aneurysm clamp. Before operation, 3D-CTA was undertaken and DSA was followed. After operation, patients were rechecked with 3D-CTA. MAIN OUTCOME MEASURES: Comparisons between 3D-CTA and DSA. RESULTS : All 106 patients were involved in the final analysis. (1) Examination of 3D-CTA and DSA: Among 118 patients with aneurysm, 110 were checked with 3D-CTA and the detected rate was 93.2% (110/118). Among other 8 cases, 3 were negative and checked again with DSA; 1 had pericallosal aneurysm, 1 ophthalmic aneurysm, and 1 anterior choroidal artery of aneurysm. 3D-CTA results of other 5 cases were suspicious, and then, they were regarded as having aneurysm with DSA. Before operation, correlation among site, body, neck of aneurysm and peripheral anatomic structure were shown sufficiently. After operation, 82 patients were rechecked with 3D-CTA, which was complete occlusion, precise, unobvious constriction, emphraxis or remains as compared with 3D-CTA those pre-operation. (2) Characteristics of 3D-CTA: With multiple vessels and angles, 3D-CTA observed the relationship between aneurysm neck and carried artery and showed thrombosis in cavity of aneurysm, calcification of aneurysm wall and peripheral structure of vessel at the same time. However, DSA could not detect the reactions mentioned above. It could delete image of cranium, simulate image of operative route, eliminate artifact induced by metal, but not distinguish blood stream direction. Meanwhile, posterior communicating artery was always poor during circle of Willis artery showing. CONCLUSION: (1) 3D-CTA is characterized by simple operation and non-invasive showing vascular stereo structure and correlation. Therefore, it is significant for diagnosis and designing plan of operative approach and focal location pre-operation and evaluating effect post-operation. (2) 3D-CTA does not completely replace DSA on the diagnosis of intracranial aneurysm. 展开更多
关键词 Preoperative diagnosis and operative effect of intracranial aneurysm with three-dimensional computed tomography angiography CTA
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Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits
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作者 Zuchao Liang Dong Wang +4 位作者 Guanghe Li Guangyu Sun Mingyu Yu Dong Xia Chunjian Ding 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期507-520,共14页
The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of signi... The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope engineering.Using the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding mass.By integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is proposed.Subsequently,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is examined.The analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear failure.The spatial form equation of the sliding mass comprises an ellipsoid and weak plane equation.The analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite slopes.Furthermore,the3D stability coefficient of the composite slope exhibits an exponential correlation with the coordinated development distance,with the coefficient gradually decreasing as the coordinated development distance increases.These findings provide a theoretical guideline for designing similar slope shape parameters and conducting stability analysis. 展开更多
关键词 Composite slope Destabilization mechanism 3D mechanical effect three-dimensional stability Coordinated development distance
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Study on the Carbon Nanotube Separative Structure for the Extended Gate H^+-Ion Sensitive Field Effect Transistor 被引量:1
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作者 Yi-Hung Liao Jung-Chuan Chou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期225-227,共3页
We use the carbon nanotube (CNT) as the material of the pH sensing layer of the separative structure for the extended gate H^+-ion sensitive field effect transistor (EGFET) device.The CNT paste was prepared with CNT p... We use the carbon nanotube (CNT) as the material of the pH sensing layer of the separative structure for the extended gate H^+-ion sensitive field effect transistor (EGFET) device.The CNT paste was prepared with CNT powder,Ag powder,silicagel,the di-n-butyl phthalate and the toluene solvents by appropriate ratio,then immobilized on the silicon substrate to form the carbon nanotube sensing layer.We measured theⅠ_(DS)-Ⅴ_G curves of the carbon nanotube separative structure EGFET device in the different pH buffer solutions by the Keithley 236Ⅰ-Ⅴmeasurement system.According to the experimental results,we can obtain the pH sensitivities of the carbon nanotube separative structure EGFET device,which is 62.54mV/pH from pH1 to pH13. 展开更多
关键词 carbon nanotube extended gate field effect transistor pH sensitivity buffer solution
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Study of Reducing Non-Ideal Effects Based on TiN Sensitive Electrode with Front-End Offset Circuit
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作者 Jung-Chuan Chou Cheng-Hsin Liu 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期248-249,共2页
The structure of the extended gate ion sensitive field effect transistor (EGISFET) is similar to the structure of the ion sensitive field effect transistor (ISFET).Moreover,the non-ideal effect of EGISFET is the mai... The structure of the extended gate ion sensitive field effect transistor (EGISFET) is similar to the structure of the ion sensitive field effect transistor (ISFET).Moreover,the non-ideal effect of EGISFET is the main impediment to development of commercial processes for sensitive devices.It is necessary to promote the stability and reliability of the devices by employing calibration circuits and the better fabrication conditions.The temporal drift exists in the entire measurement experiment. Furthermore,in this study we can reduce the temporal drift effect which influences the stability of the TiN sensitive electrode with the differential front-end offset circuit.The measurement system combines with shifting circuit,differential and instrument amplifiers.We employ the calibration circuit to compare with the variations of the output voltage,and expectably improve the stability and reliability of the TiN sensitive electrode by the novel calibration circuit. 展开更多
关键词 TiN sensitive electrode stability reliability temporal drift effect front-end offset circuit
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Design and operation strategies of the system for destroying time-sensitive target based on system effectiveness 被引量:2
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作者 Chen Jun Gao Xiaoguang Ding Lin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1151-1156,共6页
To improve the effect of destroying time-sensitive target (TST), a method of operational effectiveness evaluation is presented and some influential factors are analyzed based on the combat flow of system for destroy... To improve the effect of destroying time-sensitive target (TST), a method of operational effectiveness evaluation is presented and some influential factors are analyzed based on the combat flow of system for destroying TST. Considering the possible operation modes of the system, a waved operation mode and a continuous operation mode are put forward at first. At the same time, some relative formulas are modified. In examples, the influential factors and operation modes are analyzed based on the system effectiveness. From simulation results, some design and operation strategies of the system for destroying time sensitive targets are concluded, which benefit to the improvement of the system effectiveness. 展开更多
关键词 effectiveness evaluation time-sensitive target waved operation mode continuous operation mode
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Generalization of the theory of three-dimensional quantum Hall effect of Fermi arcs in Weyl semimetal
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作者 Mingqi Chang Yunfeng Ge Li Sheng 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期58-62,共5页
The quantum Hall effect(QHE),which is usually observed in two-dimensional systems,was predicted theoretically and observed experimentally in three-dimensional(3 D)topological semimetal.However,there are some inconsist... The quantum Hall effect(QHE),which is usually observed in two-dimensional systems,was predicted theoretically and observed experimentally in three-dimensional(3 D)topological semimetal.However,there are some inconsistencies between the theory and the experiments showing the theory is imperfect.Here,we generalize the theory of the 3 D QHE of Fermi arcs in Weyl semimetal.Through calculating the sheet Hall conductivity of a Weyl semimetal slab,we show that the 3 D QHE of Fermi arcs can occur in a large energy range and the thickness dependences of the QHE in different Fermi energies are distinct.When the Fermi energy is near the Weyl nodes,the Fermi arcs give rise to the QHE which is independent of the thickness of the slab.When the Fermi energy is not near the Weyl nodes,the two Fermi arcs form a complete Fermi loop with the assistance of bulk states giving rise to the QHE which is dependent on the sample thickness.We also demonstrate how the band anisotropic terms influence the QHE of Fermi arcs.Our theory complements the imperfections of the present theory of 3 D QHE of Fermi arcs. 展开更多
关键词 Weyl semimetal three-dimensional quantum Hall effect Fermi arcs
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The effects of three-dimensional conformal radiotherapy combined with whole brain irradiation on brain metastases
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作者 Jin Hu Yeqing Zhou Mi Liu 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第3期172-174,共3页
Objective: To observe the recently therapeutic effects and toxicity of three-dimensional conformal radiotherapy combined with whole brain irradiation for patients with brain metastasis. Methods: 33 cases were treate... Objective: To observe the recently therapeutic effects and toxicity of three-dimensional conformal radiotherapy combined with whole brain irradiation for patients with brain metastasis. Methods: 33 cases were treated by whole brain irradiation at first, the dose of which was 36-40 Gy (18-20 f). Then three-dimensional conformal radiotherapy was added to the focus with a total dose of 20-25 Gy, whose fractionated dose was 2-5 Gy/time, 5 times/week or 3 times/week. Results: Within 1 month after radiotherapy, according to imaging of the brain, the CR of all patients was 45.5%, PR 36.4%, NC 15.1%, and PD 3%. For the 32 cases with neural symptoms before radiation, the CR of the symptoms was 40.6% and PR 59.4%. All patients gained different increases in KPS grade. By the end of the follow-up period, there were 22 deaths with the mean survival time up to 9.3 months. Conclusion: Three-dimensional conformal radiotherapy combined with whole brain irradiation can not only effectively control brain metastases and improve life quality, but also tends to prolong survival time. 展开更多
关键词 brain metastasis three-dimensional conformal radiotherapy whole brain irradiation effect
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Boundary effect of toppling failure based on three-dimensional mechanical model
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作者 CAI Jun-chao ZHENG Da +2 位作者 JU Neng-pan HUANG Run-qiu ZHAO Wei-hua 《Journal of Mountain Science》 SCIE CSCD 2022年第11期3314-3322,共9页
Previous researches on the mechanical model of toppling failure mainly concentrated on twodimensional mechanical model(TwDM) analysis. The TwDM analysis assumes the width of the slab beam is unit width without conside... Previous researches on the mechanical model of toppling failure mainly concentrated on twodimensional mechanical model(TwDM) analysis. The TwDM analysis assumes the width of the slab beam is unit width without considering the lateral constraint force. The assumed conditions are obviously different from the site conditions, thus there is a certain difference between the calculated results and the field work. A three-dimensional mechanical model(ThDM)of toppling failure was established, considering that the slab beam was mainly subject to self-weight, the frictional resistance of interlayer and lateral constraint force. Due to the progressive characteristics of toppling failure, the concept and the formula of the first fracture depth(FFD) of toppling was raised and constructed. The case study indicates that the ThDM is more effective and can be accurately used to calculate the toppling fracture depth of the slab beam. The FFD decreases proportionally with the increase of slab beam width. FFD grows fast when the slab beam width is less than 2.0 m and it tends to be stable when the slab beam width is above 2.0 m. The FFD decreases with the increase of the lateral constraint coefficient, indicating that the boundary condition of the free space is positively correlated with the stability and depth of toppling. This is a good explanation of the free space effect. This study provides a reference for the stability evaluation and prevention-control design of toppling slope in the future. 展开更多
关键词 Boundary effect Toppling failure three-dimensional mechanical model(ThDM) First fracture depth(FFD) Free face Slope failure
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Three-dimensional Monte Carlo simulation of bulk fin field effect transistor
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作者 王骏成 杜刚 +2 位作者 魏康亮 张兴 刘晓彦 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期421-426,共6页
In this paper, we investigate the performance of the bulk fin field effect transistor (FinFET) through a three- dimensional (3D) full band Monte Carlo simulator with quantum correction. Several scattering mechanis... In this paper, we investigate the performance of the bulk fin field effect transistor (FinFET) through a three- dimensional (3D) full band Monte Carlo simulator with quantum correction. Several scattering mechanisms, such as the acoustic and optical phonon scattering, the ionized impurity scattering, the impact ionization scattering and the surface roughness scattering are considered in our simulator. The effects of the substrate bias and the surface roughness scattering near the Si/SiO2 interface on the performance of bulk FinFET are mainly discussed in our work. Our results show that the on-current of bulk FinFET is sensitive to the surface roughness and that we can reduce the substrate leakage current by modulating the substrate bias voltage. 展开更多
关键词 bulk fin field effect transistor (FinFET) three-dimensional (3D) Monte Carlo simulation surface roughness scattering substrate bias effect
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Effect of day length and temperature on the pollen fertility in photo(thermo)-sensitive genic male-sterile rice
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作者 HUANG Qinglui and TANG Xihua,Shanghai Inst of Piant physiology,Acad Sinica,Xhanghai 200032,China 《Chinese Rice Research Newsletter》 1996年第2期4-5,共2页
The effect of day length and temperature on the pollen fertility of five photoperiod-sensitive genic male-sterile japonica rice lines (PGMSR) and three temperature-sensitive genic malesterile indica rice lines (TGMSR)... The effect of day length and temperature on the pollen fertility of five photoperiod-sensitive genic male-sterile japonica rice lines (PGMSR) and three temperature-sensitive genic malesterile indica rice lines (TGMSR) were investigated in phytotron. The light source used for illumination was xenon lamp, and the light intensity which plant accepted on the leaf surface was 300—350μmol photons ms. The results indicated that pollens of PGMSR 7001S and E47S aborted completely whereas a little part of 31116S pollens appeared normal under long day photoperiod (LD,25℃,15h) (Table 1). High temperature (HT, 30℃, 12h) and lower temperature (LT, 展开更多
关键词 length effect of day length and temperature on the pollen fertility in photo sensitive genic male-sterile rice THERMO
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Simulation analysis on three-dimensional slope failure under different conditions 被引量:9
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作者 张科 曹平 +2 位作者 刘紫曜 胡惠华 龚道平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2490-2502,共13页
The failure mechanism of two-dimensional(2D) and three-dimensional(3D) slopes were investigated by using the strength reduction method.An extensive study of 3D effect was conducted with respect to boundary conditi... The failure mechanism of two-dimensional(2D) and three-dimensional(3D) slopes were investigated by using the strength reduction method.An extensive study of 3D effect was conducted with respect to boundary conditions,shear strength and concentrated surcharge load.The results obtained by 2D and 3D analyses were compared and the applicable scope of 2D and 3D method was analyzed.The results of the numerical simulation show that 3D effect is sensitive to the width of slip surface.As for slopes with specific geometry,3D effect is influenced by dimensionless parameter c/(γHtanφ).For those infinite slopes with local loading,external load has the major impact on failure mode.For those slopes with local loading and geometric constraints,the failure mode is influenced by both factors.With the increase of loading length,boundary condition exerts a more significant impact on the failure mode,and then 2D and 3D stability charts are developed,which provides a rapid and reliable way to calculate 2D and 3D factor of safety without iteration.Finally,a simple and practical calculation procedure based on the study of 3D effect and stability charts is proposed to recognize the right time to apply 2D or 3D method. 展开更多
关键词 three-dimensional slope slope stability three-dimensional effect strength reduction method failure mechanism
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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Time-sensitivity of the Kaiser effect of acoustic emission in limestone and its application to measurements of in-situ stress 被引量:15
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作者 Jin Yan Qi Zili Chen Mian Zhang Guangqing Xu Guangqiang 《Petroleum Science》 SCIE CAS CSCD 2009年第2期176-180,共5页
Measuring in-situ stress by using the Kaiser effect in rocks has such advantages as timeefficiency, low cost and little limitation, but the precision of the method is dependent on rock properties and delay time of the... Measuring in-situ stress by using the Kaiser effect in rocks has such advantages as timeefficiency, low cost and little limitation, but the precision of the method is dependent on rock properties and delay time of the measurement. In this paper, experiments on the Kaiser effect in limestones were performed, and it was found that the limestones had good ability to retain a memory of their recent stress history and high time-sensitivity. The longer the experiment was delayed from the extraction of the stone, the larger the Felicity ratio was. As the Felicity ratio approached l, significant Kaiser effect was observed. In-situ stress should be determined by the limestone measurements when the delay time was 40-120 days. Finally, the in-situ stress in a limestone formation could be successfully measured in practice. 展开更多
关键词 In-situ stress Kaiser effect LIMESTONE time sensitivity
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Irradiation effect on strain sensitivity coefficient of strain sensing fiber Bragg gratings 被引量:3
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作者 金靖 林松 宋凝芳 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期254-259,共6页
The effect of irradiation on the strain sensitivity coefficient of strain sensing fiber Bragg gratings (FBGs) has been investigated through experiments. FBGs were fabricated in single mode fibers with 3 tool% Ge-con... The effect of irradiation on the strain sensitivity coefficient of strain sensing fiber Bragg gratings (FBGs) has been investigated through experiments. FBGs were fabricated in single mode fibers with 3 tool% Ge-concentration in the core and with a H2-1oading treatment. In experiments, the FBGs were subjected to y-radiation exposures using a Co6~ source at a dose-rate of 25 Gy/min up to a total dose of 10.5 kGy. The GeO defect in fiber absorbs photons to form a GeE' defect; the interaction with H2 is a probable reason for the y-radiation sensitivity of gratings written in hydrogen loaded fibres, The effect mechanism of radiation on the strain sensitivity coefficient is similar to that of radiation on the temperature sensitivity coefficient. Radiation affects the effective index neff, which results in the change of the thermo-optic coefficient and the strain-optic coefficient. Irradiation can change the strain sensitivity coefficient of FBGs by 1.48%-2.71%, as well as changing the Bragg wavelength shift (BWS) by 22 pm-25 pm under a total dose of 10.5 kGy. Our research demonstrates that the effect of irradiation on the strain sensitivity coefficient of FBG is small and that strain sensing FBGs can work well in the radiation environment. 展开更多
关键词 fiber Bragg grating irradiation effect strain sensitivity coefficient
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Controls of Acid-sensitive Minerals on Reservoir Sensitivity Testing: An Example from the Silurian Kepingtage Formation in Tazhong Area, Tarim Basin 被引量:2
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作者 HAN Denglin WANG Qianqian +2 位作者 WANG Chenchen OUYANG Chuanxiang YUAN Wenfang 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期1973-1980,共8页
The Silurian Kepingtage Formation in Tazhong area is regarded as an acid-sensitive hydrocarbon reservoir. However, formation mechanism of acid-sensitive of the reservoir cannot be interpreted by the existing acid-sens... The Silurian Kepingtage Formation in Tazhong area is regarded as an acid-sensitive hydrocarbon reservoir. However, formation mechanism of acid-sensitive of the reservoir cannot be interpreted by the existing acid-sensitive evaluation criterion based on damage rate. The contents of acid-sensitive minerals illustrated by bulk-rock XRD, scanning electron microscopy and clay mineral composition analysis exert the dominant control on acid-sensitive flow testing of the reservoir. The ironbearing minerals(including pyrite cements and chlorite cements) mainly deteriorate reservoir quality, while the iron-free minerals(including calcite cements and dolomite cements) mainly improve permeability. The permeability variation of the tested samples is controlled by the relative content of two acid-sensitive minerals. On the basis of newly established sensitivity mechanism and its influence on permeability, the corresponding ion(Fe^(2+)) stabilizer was added to the acidizing fluids during the acidification reconstruction, which inhibited the negative factors of acid-sensitive minerals and improved the target layer quality effectively. 展开更多
关键词 clay mineral acidic sensitivity effect Kepingtage Formation Tazhong area
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Electrical Structure of Wulingshan and Middle Jiangnan Orogen by Three-Dimensional Magnetotelluric Data Inversion 被引量:2
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作者 RUAN Shuai YAN Jiayong +1 位作者 ZHANG Kun LV Qingtian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第S01期80-81,共2页
Funded by The National Key Research and Development Program of China,China Deep Exploration(Sinoprobe)and The China Geological Suvery Project on 2009–2019,a large scale magnetotelluric sounding(MT)survey grid(Fig.1)h... Funded by The National Key Research and Development Program of China,China Deep Exploration(Sinoprobe)and The China Geological Suvery Project on 2009–2019,a large scale magnetotelluric sounding(MT)survey grid(Fig.1)has covered whole south China. 展开更多
关键词 magnetotelluric sounding three-dimensional inversion near-field effect regularized quasi-Newton inversion Jiangnan Orogen
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Experimental Study on Vortex-Induced Vibration Coupling Wake Interference of Multi-Riser Groups with Sensitive Spacing 被引量:2
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作者 WANG Yu LI Peng +3 位作者 LIU Yu CHEN Xin LOU Min GUO Hai-yan 《China Ocean Engineering》 SCIE EI CSCD 2022年第3期333-347,共15页
The“riser group−fluid between risers”is taken as the carrier,and the experiment on vortex-induced vibration of tandem riser groups coupling interference effect under sensitive spacing is performed.The least-square m... The“riser group−fluid between risers”is taken as the carrier,and the experiment on vortex-induced vibration of tandem riser groups coupling interference effect under sensitive spacing is performed.The least-square method is used to linearly fit the reduced velocity and main frequency,and the rule of Strouhal numbers is analyzed.Each mode is separated based on the mode decomposition theory,and the mode conversion mechanism is also explored.The concept of“interference efficiency”is introduced to study the dynamic characteristics and response evolutions of different riser groups.The results show that the wake shielding effect widely exists in tandem riser groups,and the interference effect of midstream and downstream risers on their upstream risers is significantly lower than that of upstream risers on midstream and downstream risers.The trajectories of midstream and downstream risers lag behind their upstream risers due to multiple shadowing effects,the vibration frequency range of downstream riser is widened and the dominant frequency is extremely unstable.Compared with the isolated riser,wake interference suppresses the vibration dis-placement of the midstream and downstream risers in the in-line direction,and enhances the displacement of upstream and midstream risers in the cross-flow direction.The interference effect of the fluid between risers at low velocities is stronger than that at higher velocities,and the cross-flow displacements of upstream risers are always in the interference enhancement region.It is urgent to pay attention to the cross-flow displacement of upstream and midstream risers in tandem riser groups considering the safety design. 展开更多
关键词 vortex-induced vibration interference effect multi-riser groups sensitive spacing tandem arrangement dynamic response
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