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Hypoglycaemia in screening oral glucose tolerance test in pregnancy with low birth weight fetus
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作者 Nicoleta Gana Iulia Huluta Nicolae Gica 《World Journal of Experimental Medicine》 2024年第3期119-121,共3页
Maternal hypoglycemia,a condition characterized by lower than normal blood glucose levels in pregnant women,has been increasingly associated with adverse pregnancy outcomes,including low birth weight(LBW)in neonates.L... Maternal hypoglycemia,a condition characterized by lower than normal blood glucose levels in pregnant women,has been increasingly associated with adverse pregnancy outcomes,including low birth weight(LBW)in neonates.LBW,defined as a birth weight of less than 2500 g,can result from various factors,including maternal nutrition,health status,and metabolic conditions like hypoglycemia.Maternal hypoglycemia may affect fetal growth by altering the supply of essential nutrients and oxygen to the fetus,leading to restricted fetal development and growth.This condition poses significant risks not only during pregnancy but also for the long-term health of the child,increasing the likelihood of developmental delays,health issues,and chronic conditions later in life.Research in this area has focused on understanding the mechanisms through which maternal hypoglycemia influences fetal development,with studies suggesting that alterations in placental blood flow and nutrient transport,as well as direct effects on fetal insulin levels and metabolism,may play a role.Given the potential impact of maternal hypoglycemia on neonatal health outcomes,early detection and management are crucial to minimize risks for LBW and its associated complications.Further investigations are needed to fully elucidate the complex interactions between maternal glucose levels and fetal growth,as well as to develop targeted interventions to support the health of both mother and child.Understanding these relationships is vital for improving prenatal care and outcomes for pregnancies complicated by hypoglycemia. 展开更多
关键词 Glucose tolerance test low birth weight HYPOGLYCAEMIA High-risk pregnancy Neonatal outcome
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Pilot Test for Nitrogen Foam Flooding in Low Permeability Reservoir
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作者 Xinyu Zhou Jia Huang +5 位作者 Yuchen Qian Wenli Luo Lisha Qi Jie Wang Zhibin Jiang Hao Kang 《Energy Engineering》 EI 2023年第3期763-774,共12页
Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the ti... Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very low.It is hard to obtain high recovery through conventional development schemes.Considering the tight matrix,complex fracture system,low production level of producers,and low recovery factor ofMblock in Xinjiang oilfield,it is selected for on-site pilot test of nitrogen foam flooding.Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors.The pressure index,filling degree,and fluid injection profile are found to be all improved in injectors after injection of nitrogen foam.The oil production,water cut and liquid production file are also improved in most of the producers,with the natural decline rate in the test area become slow.Results show that nitrogen foam flooding technology can be good technical storage for enhanced oil recovery in low permeability reservoir. 展开更多
关键词 Fluid production profile nitrogen foam low permeability pilot test
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Research on Well Testing Interpretation of Low Permeability Deformed Dual Medium Reservoir
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作者 Meinan Wang Yue Xie +2 位作者 Rui Zhang Guohao Zhang Jianguo Liu 《Open Journal of Applied Sciences》 2023年第11期2141-2148,共8页
Considering the influence of quadratic gradient term and medium deformation on the seepage equation, a well testing interpretation model for low permeability and deformation dual medium reservoirs was derived and esta... Considering the influence of quadratic gradient term and medium deformation on the seepage equation, a well testing interpretation model for low permeability and deformation dual medium reservoirs was derived and established. The difference method was used to solve the problem, and pressure and pressure derivative double logarithmic curves were drawn to analyze the seepage law. The research results indicate that the influence of starting pressure gradient and medium deformation on the pressure characteristic curve is mainly manifested in the middle and late stages. The larger the value, the more obvious the upward warping of the pressure and pressure derivative curve;the parameter characterizing the dual medium is the crossflow coefficient. The channeling coefficient determines the time and location of the appearance of the “concave”. The smaller the value, the later the appearance of the “concave”, and the more to the right of the “concave”. 展开更多
关键词 low Permeability Oil Reservoirs Deformation Medium Dual Media Cross Flow Coefficient Well testing Interpretation Model
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Temperature Control and Simulation of Temperature-Altitude Test System 被引量:1
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作者 Yuan Lingshuang,Liu Meng,Wang Jun(School of Aeronautics Science and Engineering,Beijing University ofAeronautics and Astronautics,Beijing 100083,China) 《工程科学(英文版)》 2007年第3期91-94,100,共5页
The temperature-Altitude Test System(TATS) supplies various testing environments.The traditional PID method controls the temperature in TATS Temperature-Pressure Cabin(TPC) over a long adjusting time and with a large ... The temperature-Altitude Test System(TATS) supplies various testing environments.The traditional PID method controls the temperature in TATS Temperature-Pressure Cabin(TPC) over a long adjusting time and with a large overshoot.In order to solve this problem simply,a temperature control strategy with temperature difference corresponding factors is presented through a dynamic analysis and modeling of TPC temperature change.The TPC temperature descending process is simulated,and the results show that this control strategy can allot the proportion of PID heating controller and PID cooling controller in the whole control process and TPC temperature can be controlled at a set point quickly and effectively. 展开更多
关键词 temperature-altitude ENVIRONMENTAL test TEMPERATURE controlling simulation CORRESPONDING FACTOR
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Similarity model tests of movement and deformation of coal-rock mass below stopes 被引量:6
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作者 WANG, Haifeng CHENG, Yuanping +1 位作者 YUAN, Liang WANG, Liang 《Mining Science and Technology》 EI CAS 2010年第2期188-192,共5页
For a study of the movement and deformation of coal-rock mass and low protected seams below a stope,as well as for fracture developments and rules of evolution of permeability,we designed a plane strain model test sta... For a study of the movement and deformation of coal-rock mass and low protected seams below a stope,as well as for fracture developments and rules of evolution of permeability,we designed a plane strain model test stand to carry out model tests of similar materials in order to improve the effect of gas drainage from low protected seams and to measure the movement and deformation of coal-rock mass using a method of non-contact close-range photogrammetry.Our results show that 1) using paraffin melting to take the place of coal seam mining can satisfy the mining conditions of a protective seam;2) coal-rock mass under goafs has an upward movement after the protective seam has been mined,causing floor heaving;3) low protected seams become swollen and deformed,providing a good pressure-relief effect and causing the coal-rock mass under both sides of coal pillars to become deformed by compression and 4) the evolution of permeability of low protected seams follows the way of initial values→a slight decrease→a great increase→stability→final decrease.Simultaneously,the coefficient of air permeability increased at a decreasing rate with an increase in interlayer spacing. 展开更多
关键词 coal-rock mass below stope low protected seam plane strain similar model test
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Association of hypoglycaemia in screening oral glucose tolerance test in pregnancy with low birth weight fetus 被引量:2
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作者 Ananth U Nayak Arun M A Vijay +3 位作者 Radha Indusekhar Sushuma Kalidindi Venkata M Katreddy Lakshminarayanan Varadhan 《World Journal of Diabetes》 SCIE CAS 2019年第5期304-310,共7页
BACKGROUND Gestational diabetes mellitus(GDM) is a common metabolic derangement in pregnant women. In the women identified to be at high risk of GDM, a 75 g oral glucose tolerance test(OGTT) at 24-28 wk gestation is t... BACKGROUND Gestational diabetes mellitus(GDM) is a common metabolic derangement in pregnant women. In the women identified to be at high risk of GDM, a 75 g oral glucose tolerance test(OGTT) at 24-28 wk gestation is the recommended screening test in the United Kingdom as per National Institute for Health and Care Excellence(NICE). Hypoglycaemia following the glucose load is often encountered and the implication of this finding for the pregnancy, fetus and clinical care is unclear.AIM To determine the prevalence of hypoglycaemia at any time during the screening OGTT and explore its association with birth weight.METHODS All deliveries between 2009 and 2013 at the local maternity unit of the University hospital were reviewed. Of the total number of 24,154 women without preexisting diabetes, those who had an OGTT for GDM screening based on NICE recommended risk stratification, who had a singleton delivery and had complete clinical and demographic data for analysis, were included for this study(n =3537). Blood samples for fasting plasma glucose(FPG), 2-hour plasma glucose(2-h PG) and HbA1 c had been obtained. Birth weight was categorised as low(≤ 2500 g), normal or Macrosomia(≥ 4500 g) and blood glucose ≤ 3.5 mmol/L was used to define hypoglycaemia. Binary logistic regression was used to determine the association of various independent factors with dichotomized variables; the differences between frequencies/proportions by χ~2 test and comparison between group means was by one-way ANOVA.RESULTS Amongst the study cohort(3537 deliveries), 96(2.7%) women had babies with LBW(< 2500 g). Women who delivered a LBW baby had significantly lower FPG(4.3 ± 0.6 mmol/L, P = 0.001). The proportion of women who had a 2-h PG ≤ 3.5 mmol/L in the LBW cohort was significantly higher compared to the cohorts with normal and macrosomic babies(8.3% vs 2.8% vs 4.2%; P = 0.007). The factors which predicted LBW were FPG, Asian ethnicity and 2-h PG ≤ 3.5 mmol/L,whereas maternal age, 2-h PG ≥ 7.8 mmol/L and HbA1c were not significant predictors.CONCLUSION A low FPG and 2-h PG ≤ 3.5 mmol/L on 75-gram OGTT are significantly associated with low birth weight in women identified as high risk for GDM.Women of ethnic backgrounds(Asians) appear to be more susceptible to this increased risk and may serve as a separate cohort in whom we should offer more intensive follow up and screening for complications. Cost implications and resources for follow up would need to be looked at in further detail to support these findings. 展开更多
关键词 HYPOGLYCEMIA GLUCOSE tolerance test low BIRTH weight PREGNANCY
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Effect of SACMA and QMW Test Methods on Compressive Properties of Composite Laminates after Low Velocity Impact 被引量:2
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作者 CHENG Xiao-quan ZHANG Zi-long +1 位作者 YI Xiao-su WU Xue-ren 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2002年第2期90-97,共8页
Experimental studies on the compressive behavior of composite laminates after low velocity impact was carried out with two test methods.One is SACMA Standard,and the other is a small dimensional specimen test method.I... Experimental studies on the compressive behavior of composite laminates after low velocity impact was carried out with two test methods.One is SACMA Standard,and the other is a small dimensional specimen test method.Impact damage distributions,compressive failure process after impact,quasi static indentation and compression of laminates with a hole were brought into comparison between these two test methods.The results showed that there is a great difference between these two test methods.Compressive behavior of laminates after impact varies with different test methods.Residual compressive strength of laminates after low velocity impact measured with SACMA Standard can reflect stiffness properties of composite resins more wholely than that measured with the other method can do.Small dimensional specimen test method should be improved on as an experimental standard of compressive strength after impact. 展开更多
关键词 composite laminates test methods low velocity impact DAMAGE residual compressive strength
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Dependence of single event upsets sensitivity of low energy proton on test factors in 65 nm SRAM 被引量:1
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作者 Yin-Yong Luo Feng-Qi Zhang +2 位作者 Xiao-Yu Pan Hong-Xia Guo Yuan-Ming Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期566-571,共6页
In order to accurately predict the single event upsets (SEU) rate of on-orbit proton, the influence of the proton energy distribution, incident angle, supply voltage, and test pattern on the height, width, and posit... In order to accurately predict the single event upsets (SEU) rate of on-orbit proton, the influence of the proton energy distribution, incident angle, supply voltage, and test pattern on the height, width, and position of SEU peak of low energy protons (LEP) in 65 nm static random access memory (SRAM) are quantitatively evaluated and analyzed based on LEP testing data and Monte Carlo simulation. The results show that different initial proton energies used to degrade the beam energy will bring about the difference in the energy distribution of average proton energy at the surface and sensitive region of the device under test (DUT), which further leads to significant differences including the height of SEU peak and the threshold energy of SEU. Using the lowest initial proton energy is extremely important for SEU testing with low energy protons. The proton energy corresponding to the SEU peak shifts to higher average proton energies with the increase of the tilt angle, and the SEU peaks also increase significantly. The reduction of supply voltage lowers the critical charge of SEU, leading to the increase of LEP SEU cross section. For standard 6-transitor SRAM with bit-interleaving technology, SEU peak does not show clear dependence on three test patterns of logical checkerboard 55H, all" 1", and all "0". It should be noted that all the SEUs in 65 nm SRAM are single cell upset in LEP testing due to proton's low linear energy transfer (LET) value. 展开更多
关键词 low energy proton energy distribution tilt angle supply voltage test pattern
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High-frequency interference waves in low strain dynamic testing of X-section concrete piles 被引量:1
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作者 Qu Liming Fan Yuming +2 位作者 Ding Xuanming Yang Changwei Zhang Yanling 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第4期877-885,共9页
Stress waves propagate along vertical,radial and circumferential directions when a non-uniformly distributed load is applied at one end of a three-dimensional shaft.As a result,the receiving signals are usually mixed ... Stress waves propagate along vertical,radial and circumferential directions when a non-uniformly distributed load is applied at one end of a three-dimensional shaft.As a result,the receiving signals are usually mixed with undesired interference components,often featuring as high-frequency fluctuations.Previous studies have revealed that sectional geometry(shape and size)greatly affects the high-frequency interference.In this study,low strain dynamic testing on full-scale X-section concrete is conducted in order to investigate the influences of high-frequency interference on velocity responses at the pile head.Emphasis is placed on the frequency and peak value of interference waves at various receiving points.Additionally,the effects of the geometrical,and mechanical properties of the pile shaft on high-frequency interference are elaborated on through the three-dimensional finite element method.The results show that the measured wave is obscured by interference waves superposed by two types of high-frequency components.The modulus and cross-sectional area are contributing factors to the frequency and peak value of the interference waves.On the other hand,the position with the least interference is determined,to some extent,by the accurate shape of the X-section. 展开更多
关键词 low strain dynamic testing X-section concrete pile high-frequency interference full-scale model test finite element method
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Heap-Leaching of Low-Grade Uranium Ore at SOMAIR: From Laboratory Tests to Production of 700 Tonnes U Per Year
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作者 Nicolas Durupt Jean Jacques Blanvillain 《Journal of Chemistry and Chemical Engineering》 2011年第6期549-557,共9页
In 2006, SOMAIR decided to increase the uranium production by 50% using heap leaching for the treatment of low grade ores. These ores, which come from different lodes with various properties, have been studied in four... In 2006, SOMAIR decided to increase the uranium production by 50% using heap leaching for the treatment of low grade ores. These ores, which come from different lodes with various properties, have been studied in four steps: ( 1 ) Lab tests: to compare the ores (characterization, acid consumptions, recovery...); (2) Column tests on an average sample: to define significant parameters for a feasibility study; (3) Column tests on specific samples: to optimize recovery for each ore and identify problems of percolation due to the clays; (4) Pilot tests in large boxes (stalls): to validate process parameters. Uranium production by heap leaching started in July 2009. 展开更多
关键词 URANIUM heap-leaching low grade ores clays column tests acid consumption.
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Effect of Verbal Instructions in Pain Assessment during a Passive Straight Leg Raise Test in People with Chronic Low Back Pain
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作者 Masae Ikeya Takumi Jiroumaru +3 位作者 Hitomi Bunki Michio Wachi Noriyuki Kida Teruo Nomura 《Open Journal of Therapy and Rehabilitation》 2022年第4期189-197,共9页
The most prevalent issue in physical therapy is pain. Due to the subjective nature of pain, assessment tools are essential in understanding it as objective data. However, assessment of pain may result in distress for ... The most prevalent issue in physical therapy is pain. Due to the subjective nature of pain, assessment tools are essential in understanding it as objective data. However, assessment of pain may result in distress for the patient. A physical therapist (PT) should conduct these tests as quickly and accurately as possible. Straightforward instructions are vital in such cases. This study aimed to clarify the effect of verbal instructions for pain assessment during a passive straight leg raise (PSLR) test for participants with chronic low back pain (CLBP). This study included 22 participants who provided informed consent and received three consecutive PSLR tests with measurement of the hip flexion range of motion (HFROM) and were instructed to cease the test at submaximal pain before the first test. Following the second and third tests, participants were given specific verbal instructions to remember pain intensity, quality, and location. After each test, participants were to circle the pain location on the body chart and rate their pain intensity on a numeric rating scale (NRS) and pain quality. All participants were then interviewed about the differences between having and not having specific verbal instructions. The results of HFROM, NRS, and pain extent were not significantly different between the first and second tests or between the second and third tests using a paired t-test. Eleven changes in pain location were found in the second test compared to those in the first test. In the third test, only three participants circled a different area than in the second test. Ten participants showed similar changes with pain location in pain quality in the three PSLR tests. This study revealed the effect of specific verbal instructions prior to PSLR tests. Particularly, participants could notice exact pain location. Our findings may help PT to understand pain cause and reduce patients’ stress during pain assessment in clinical settings. 展开更多
关键词 Chronic low Back Pain Pain Assessment Passive Straight Leg Raise test Verbal Instructions
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Design for Low Power Testing of Computation Modules with Contiguous Subspace in VLSI
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作者 Ji-Xue Xiao Yong-Le Xie Guang-Ju Chen 《Journal of Electronic Science and Technology of China》 2009年第4期326-330,共5页
A kind of pseudo Gray code presentation of test patterns based on accumulation generators is presented and a low power test scheme is proposed to test computational function modules with contiguous subspace in very la... A kind of pseudo Gray code presentation of test patterns based on accumulation generators is presented and a low power test scheme is proposed to test computational function modules with contiguous subspace in very large scale integration (VLSI), especially in digital signal processors (DSP). If test patterns from accumulators for the modules are encoded in the pseudo Gray code presentation, the switching activities of the modules are reduced, and the decrease of the test power consumption is resulted in. Results of experimentation based on FPGA show that the test approach can reduce dynamic power consumption by an average of 17.40% for 8-bit ripple carry adder consisting of 3-2 counters. Then implementation of the low power test in hardware is exploited. Because of the reuse of adders, introduction of additional XOR logic gates is avoided successfully. The design minimizes additional hardware overhead for test and needs no adjustment of circuit structure. The low power test can detect any combinational stuck-at fault within the basic building block without any degradation of original circuit performance. 展开更多
关键词 ADDER design digital signal processors (DSP) low power test.
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Test evaluation for vertical fracture wells in low permeability reservoir
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作者 CUI Li-ping HE Shun-li 《Journal of Energy and Power Engineering》 2009年第9期32-35,共4页
As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test a... As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test analysis methods are of slow fitting speed and low fitting precision. In this paper, we first use a comprehensive evaluation method of analytical well testing, numerical well testing and well testing design. Many dynamic parameters such as fracture length, fracture conductivity, skin factor, etc are obtained. An example to illustrate accurate results of this method is given. 展开更多
关键词 test evaluation fracture wells low permeability reservoir fracturing effect
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Pilot-test about Treatment of Low-concentration Organic Waste Gas Using a Fixed Biological Bed
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作者 Wei Zhang Xu Zhang +2 位作者 Jun Ma Yajuan Zhu Zhuo Huang 《Meteorological and Environmental Research》 CAS 2013年第4期53-55,共3页
[ Objective] The study aims to discuss the feasibility of using a fixed biological bed to treat low-concentration organic waste gas. [ Method] A fixed biological bed was used to treat low-concentration organic waste g... [ Objective] The study aims to discuss the feasibility of using a fixed biological bed to treat low-concentration organic waste gas. [ Method] A fixed biological bed was used to treat low-concentration organic waste gas from a phosphate workshop, and then the waste gas treated was assessed by human sense of smell to determine the most economical empty bed contact time, thereby verifying the feasibility of using a fixed biolog- ical bed to treat low-concentration organic waste gas. [Result] When empty bed contact time was 60 s, the smell of the treated waste gas was acceptable, and COD value of recycled water in the fixed biological bed was essentially unchanged. It proved that organic load of the waste gas was consumed by microorganisms within 60 s. [ Conclusion] It is feasible to use a fixed biological bed to treat Iow-concantration organic waste gas from a phosphate workshop. 展开更多
关键词 Fixed biological bed low-concentration organic waste gas Pilot-test China
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Pre-exposure effect of low-dose ^(16)O^(8+) or γ-rays on testicular endocrine of mice
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作者 ZhangHong ZhengRong-Liang 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第1期47-48,共2页
Preexposureefectoflowdose16O8+orγraysontesticularendocrineofmiceZhangHong,WeiZengQuan,LiWenJian,ChenWeiQiang... Preexposureefectoflowdose16O8+orγraysontesticularendocrineofmiceZhangHong,WeiZengQuan,LiWenJian,ChenWeiQiang,LiangJi... 展开更多
关键词 低剂量γ-射线 老鼠内分泌 预照射效应
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基于碰撞特性的鲜食玉米摘穗装置对比试验 被引量:1
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作者 张红梅 陈博 +3 位作者 胡经营 李志杰 何勋 王万章 《河南农业大学学报》 CAS CSCD 北大核心 2024年第1期87-95,共9页
【目的】探究缓冲弹簧和柔性触穗表面两种摘穗机构在摘取果穗中的低损作用及机制。【方法】以传统玉米收获用板式摘穗机构和具有缓冲弹簧加柔性触穗表面的柔性摘穗机构为2种摘穗结构,以刚性触穗表面、柔性橡胶触穗表面、柔性发泡材料触... 【目的】探究缓冲弹簧和柔性触穗表面两种摘穗机构在摘取果穗中的低损作用及机制。【方法】以传统玉米收获用板式摘穗机构和具有缓冲弹簧加柔性触穗表面的柔性摘穗机构为2种摘穗结构,以刚性触穗表面、柔性橡胶触穗表面、柔性发泡材料触穗表面为3种触穗表面,得出6种摘穗机构,进行鲜食玉米果穗碰撞试验,采集和分析碰撞时间、碰撞加速度峰值,计算碰撞冲量,统计籽粒破碎率。【结果】柔性摘穗机构能够有效降低鲜食玉米果穗受到的碰撞时间,从而降低鲜食玉米果穗的籽粒破碎率。缓冲弹簧可缩短鲜食玉米果穗的碰撞时间,当柔性摘穗机构表面为柔性橡胶和柔性发泡材料时,碰撞时间分别比板式摘穗机构降低了66.2%、70.1%和70.1%。碰撞冲量分别降低了67.6%、77.9%和79.7%。籽粒破碎率降低了71.2%、51.3%和83.6%。对于柔性摘穗机构,鲜食玉米果穗与柔性橡胶、柔性发泡材料触穗表面的碰撞时间比刚性触穗表面分别延长了58.7%和63.2%。碰撞加速度峰值分别降低了62.5%和68.7%。碰撞冲量分别降低了42.4%和54.5%。籽粒破碎率分别降低了47.4%和68.4%。【结论】通过降低收获过程中鲜食玉米果穗受到的碰撞时间和碰撞加速度,从而有效降低了鲜食玉米果穗的籽粒破碎率,为鲜食玉米低损收获机的研制提供理论依据和设计参考。 展开更多
关键词 鲜食玉米 柔性摘穗 低损 碰撞试验
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轻钢龙骨混凝土复合外挂墙板力学性能试验研究 被引量:1
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作者 魏晓斌 郭建祥 +2 位作者 汤东婴 孙正华 汪晟 《结构工程师》 2024年第1期99-106,共8页
复合墙板性能关系着结构的安全,在新设计建造的轻钢龙骨复合墙板投入使用前应进行力学性能试验,以评估其安全性能。为研究墙板的受力变形过程及破坏形态,对两片不同的轻钢龙骨混凝土复合外挂墙板分别进行四点弯曲试验和低周反复荷载试... 复合墙板性能关系着结构的安全,在新设计建造的轻钢龙骨复合墙板投入使用前应进行力学性能试验,以评估其安全性能。为研究墙板的受力变形过程及破坏形态,对两片不同的轻钢龙骨混凝土复合外挂墙板分别进行四点弯曲试验和低周反复荷载试验。弯曲试验结果表明,弯曲过程中墙板出现裂缝时的计算等效均布荷载大于建筑风荷载标准值,抗弯性能满足受力要求。墙板经历了弹性阶段、弹塑性变形阶段和屈服破坏阶段,主要通过钢材屈服后的弹塑性变形和材料的破坏来实现耗能,屈服前耗能占总耗能的6.19%,屈服后累计耗能呈现二次抛物线增长,这一结果体现了墙板良好的抗震能力。研究结果可为实际应用提供依据。 展开更多
关键词 墙板 力学性能 抗弯试验 低周反复试验
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新型钢管混凝土梁柱节点力学性能试验研究 被引量:2
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作者 张晓光 曹国旭 +1 位作者 黄远 李乾坤 《建筑结构》 北大核心 2024年第3期1-6,共6页
为研究内加强环式圆钢管混凝土柱与矩形钢管混凝土梁这种新型连接节点的力学性能,设计了缩尺钢管混凝土梁柱节点试件,开展了相同梁柱节点试件的静力加载试验和低周往复加载试验。通过研究该节点试件的破坏模式、荷载-位移曲线以及拟静... 为研究内加强环式圆钢管混凝土柱与矩形钢管混凝土梁这种新型连接节点的力学性能,设计了缩尺钢管混凝土梁柱节点试件,开展了相同梁柱节点试件的静力加载试验和低周往复加载试验。通过研究该节点试件的破坏模式、荷载-位移曲线以及拟静力加载试验的骨架曲线、核心区剪切变形等,分析了节点试件的承载能力、延性和耗能能力,全面考察了同一梁柱节点在静力加载和低周往复加载两种工况下的受力性能和破坏模式。结果表明:钢管混凝土梁柱节点试件核心区强度较强,破坏模式主要为梁端破坏,低周往复加载试验时试件梁柱连接处附近的梁端钢板发生拉裂破坏和钢板鼓曲,静力加载试验时试件梁端焊缝发生拉裂破坏;试件延性较好,加载过程中经历了弹性、弹塑性和塑性发展阶段。最后提出了该类钢管混凝土梁柱节点核心区的抗剪强度计算公式。 展开更多
关键词 钢管混凝土梁柱节点 内隔板 静力加载试验 低周往复加载试验 受力性能 设计方法
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寒冷地区Low-E节能玻璃检测与应用技术研究
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作者 王磊 杨德壮 郑德玉 《建设科技》 2023年第3期32-35,共4页
通过对Low-E节能玻璃传热系数的检测,找出影响Low-E中空玻璃传热系数K值的因素,生产企业可以根据这些因素择优制作Low-E节能玻璃。本文还给出常用玻璃与窗框配合后整窗传热系数K值,绿色建筑、超低能耗绿色建筑所用外窗的适配窗框与Low-... 通过对Low-E节能玻璃传热系数的检测,找出影响Low-E中空玻璃传热系数K值的因素,生产企业可以根据这些因素择优制作Low-E节能玻璃。本文还给出常用玻璃与窗框配合后整窗传热系数K值,绿色建筑、超低能耗绿色建筑所用外窗的适配窗框与Low-E节能玻璃一目了然。 展开更多
关键词 寒冷地区 low-E节能玻璃 检测 应用技术
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新形势下航天装备环境试验技术的未来发展趋势
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作者 吴建国 李海波 +1 位作者 冯国林 姚艺豪 《装备环境工程》 CAS 2024年第5期34-40,共7页
从航天装备面临的实战化考核、数字化建设和低成本控制等新形势与新要求出发,梳理了环境试验技术在航天装备试验鉴定中存在的实战化考核能力不足、全寿命周期环境效应考核不充分等技术难题,结合航天装备环境试验的国内外发展现状,系统... 从航天装备面临的实战化考核、数字化建设和低成本控制等新形势与新要求出发,梳理了环境试验技术在航天装备试验鉴定中存在的实战化考核能力不足、全寿命周期环境效应考核不充分等技术难题,结合航天装备环境试验的国内外发展现状,系统分析了航天装备环境试验技术的未来发展趋势,试验环境综合化、试验设计一体化、试验手段数字化在提升航天装备环境试验水平、缩短装备试验周期、降低试验成本方面具有显著优势,也是航天装备环境试验未来发展的重要方向。 展开更多
关键词 环境试验 实战化 数字化 一体化 低成本
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