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A Preliminary Study on Dynamics and Models of N,P,K Absorption for High-Yield Cotton 被引量:6
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作者 WANGKe-ru LIShao-kun +3 位作者 CAOLian-pu SONGGuang-jie CHENGang CAOSuan-zhu 《Agricultural Sciences in China》 CAS CSCD 2003年第7期752-759,共8页
The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of ... The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of N, P2O5, K2O in cotton leaves, stems, squares and bolls decreased obviously with the time over the whole growth duration and the falling extent was greater in high-yield cotton than in CK. Contents of N in leaves, squares and bolls, in particular in the leaves of fruit-bearing shoot was higher in high-yield cotton than in CK. Contents of P2O5 in squares and bolls and that of K2O in stems were higher in high-yield cotton than in CK during the whole growing period. The accumulations of N, P2O5 and K2O in the cotton plants could be described with a logistic curve equation. There was the fastest nutrient uptake at about 90 d for N, 92 d for P2O5 and 85 d for K2O after emergence, respectively. Total nutrient accumulation of N, P2O5 and K2O was 385.8, 244. 7 and 340.3 kg ha-1, respectively. Approximately 12. 5 kg N, 8. 0 kg P2O5 and 11.1 kg K2O were needed for producing 100 kg lint with the leaves and stems under the super high yield condition of 3 000 kg ha-1 in Xinjiang. 展开更多
关键词 XINJIANG Cultivation of high yield COTTON N P K absorption dynamics Model
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Infrared Absorption and [CuO_5] Pyramid of High T_c Superconductor Bi-Sb-Sr-Ca-Cu-O System
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作者 宋桂兰 朱正芳 白培光 《Journal of Beijing Institute of Technology》 EI CAS 1996年第1期63-67,共5页
The infrared absorption spectra of different superconducting phase of high Tc super conductor Bi-Sb-Sr-Ca-Cu-O have been measured . The results show that only in the range of 400cm-1 -700cm-1,there is a group of peaks... The infrared absorption spectra of different superconducting phase of high Tc super conductor Bi-Sb-Sr-Ca-Cu-O have been measured . The results show that only in the range of 400cm-1 -700cm-1,there is a group of peaks which changes with different superconducting phases.According to group theory and infrared spectra of CuO, this group of peaks could be assigned to be the [CuO6]octahedron, the [CuO5] pyramid and the [CuO4]plane quadrilateral,but not CU-O plane or CU-O chain. Furthermore, the quasi-three dimensional Cu-O layers consisting of [CuO5] pyramids and proper coupling between them are essential factor for high Tc. It seems that the weaker compling of layers, the higher Tc 展开更多
关键词 infrared absorption high temperature superconductivity [CuO_5] pyramid structure
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Comparison of Phosphorous Absorption, Quality and Yield Between High Oil Corn and Common Corn as Influenced by Phosphorous Application 被引量:1
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作者 HEPing JINJi-yun +5 位作者 LIWen-juan LIUHai-long HUANGShao-wen WANGXiu-fang WANGLi-chun XIEJia-gui 《Agricultural Sciences in China》 CAS CSCD 2005年第5期376-381,共6页
A field trial was carried out to investigate phosphorous (P) absorption, grain quality and yield between high oil corn and common corn. The results indicated that high oil corn var.Tongyou 1 obtained lower highest P a... A field trial was carried out to investigate phosphorous (P) absorption, grain quality and yield between high oil corn and common corn. The results indicated that high oil corn var.Tongyou 1 obtained lower highest P absorption rate (HAR) and later occurring date of HAR, in comparison with common corn var. Simi 25. The highest HAR and the earliest occurring date of HAR was obtained by the treatments of P45 and P75 in Tongyou 1 and Simi 25 separately; while the total amount of P accumulated by maize plant was achieved by P105 treatment in both varieties. P in grain relied mainly on root uptake at maturation that accounted for 85.7-96.8% and 79.3-84.3% for Tongyou 1 and Simi 25, respectively. Tongyou 1 contained more oil and protein contents, but less starch content with lower grain yield. P application at appropriate rate enhanced contents of protein and fatty acid, but the increment of starch content was neglectable. Acknowledgements This study was financed by the National Key Tech- nologies R & D Program (2004BA520A13), P.R.China. 展开更多
关键词 high oil corn Phosphorous application Phosphorous absorption QUALITY YIELD
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Influence of osmotic distillation on membrane absorption for the treatment of high strength ammonia wastewater 被引量:1
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作者 WANGGuan-ping SHIHan-chang SHENZhi-song 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期651-655,共5页
Osmotic distillation(OD) was found to be a coupled process in membrane absorption(MA) for the treatment of high strength ammonia wastewater. As a result, ammonia could not be concentrated in absorption solution(AS) as... Osmotic distillation(OD) was found to be a coupled process in membrane absorption(MA) for the treatment of high strength ammonia wastewater. As a result, ammonia could not be concentrated in absorption solution(AS) as expected. The inhibition of the coupled OD in MA process was investigated as well as various factors affecting the inhibition. The results indicated that the coupled OD can be effectively inhibited by heating concentrated solution and cooling dilute solution. It was also found that experimental minimum inhibition temperature difference(MITD) between concentrated and dilute solutions was different when using polyvinylidene fluoride(PVDF) and polypropylene(PP) membranes respectively, which could be ascribed to material properties, such as OD and membrane distillation(MD) coefficients of the membranes. Experimental MITDs were found to be higher than theoretical MITDs which were calculated using a simplified method. 展开更多
关键词 membrane absorption osmotic distillation high strength ammonia wastewater
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Improved Visible Transparency of SiO_2/ZnO:Al/CeO_2-TiO_2/SiO_2 Multilayer Films with High UV Absorption and Infrared Reflection Rate 被引量:1
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作者 倪佳苗 赵修建 +1 位作者 ZHAO Qingnan ZHENG Mindong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期941-946,共6页
New visible transparent, UV absorption, and high infrared reflection properties have been realized by depositing multilayer Si O2/Zn O: Al/Ce O2-Ti O2/Si O2 films onto glass substrates at low temperature by radio freq... New visible transparent, UV absorption, and high infrared reflection properties have been realized by depositing multilayer Si O2/Zn O: Al/Ce O2-Ti O2/Si O2 films onto glass substrates at low temperature by radio frequency magnetron sputtering. Optimum thickness of Si O2, Zn O: Al(ZAO) and Ce O2-Ti O2(CTO) films were designed with the aid of thin film design software. The degree of antireflection can be controlled by adjusting the thickness and refractive index. The outer Si O2 film can diminish the interference coloring and increase the transparency; the inner Si O2 film improves the adhesion of the coating on the glass substrate and prevents Ca2+, Na+ in the glass substrate from entering the ZAO film. The average transmittance in the visible light range increases by nearly 18%-20%, as compared to double layer ZAO/CTO films. And the films display high infrared reflection rate of above 75% in the wavelength range of 10-25 μm and good UV absorption(> 98%) properties. These systems are easy to produce on a large scale at low cost and exhibit high mechanical and chemical durability. The triple functional films with high UV absorption, antireflective and high infrared reflection rate will adapt to application in flat panel display and architectural coating glass, automotive glass, with diminishing light pollution as well as decreasing eye fatigue and increasing comfort. 展开更多
关键词 Si O2/Zn O:Al /Ce O2-Ti O2/Si O2 TRANSPARENCY high infrared reflection rate ultraviolet absorption optimization
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Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators
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作者 Chenyang Xing Zihao Li +4 位作者 Ziao Wang Shaohui Zhang Zhongjian Xie Xi Zhu Zhengchun Peng 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期149-168,共20页
The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns.However,the nanosized Te(... The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns.However,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface structures.Herein,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic liquid.Anions,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk Te.The resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light absorption.We also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun irradiation.Furthermore,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions. 展开更多
关键词 TELLURIUM high entropy Electrochemical modification Solar absorption Evaporation rate
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Extreme Light Concentration and High Absorption of the Double Cylindrical Microcavities
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作者 衡航 王嵘 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期49-53,共5页
We numerically study the enhancement factor of energy density and absorption efficiency inside the double cylindrical microcavities based on a triple-band metamaterial absorber. The compact single unit cell consists o... We numerically study the enhancement factor of energy density and absorption efficiency inside the double cylindrical microcavities based on a triple-band metamaterial absorber. The compact single unit cell consists of concentric gold rings with a gold disk in the center and a metallic ground plane separated by a dielectric layer. We demonstrate that the multilayer structure with subwavelength electromagnetic confinement allows 104-105-fold enhancement of the electromagnetic energy density inside the double cavities and contains the most energy of the incoming light. Particularly, the enhancement factor of energy density G shows strong ability of localizing light and some regularity as the change of the thickness of the dielectric slab and dielectric constant. At the normal incidence of electromagnetic radiation, the obtained reflection spectra show that the resonance frequencies of the double microcavities operate in the range of 10-30μm. We also calculate the absorption efficiency C, which can reach 95%, 97% and 95% at corresponding frequency by optimizing the structure's geometry parameters. Moreover, the proposed structure will be insensitive to the polarization of the incident wave due to the symmetry of the double cylindrical microcavities. The proposed optical metamaterial is a promising candidate as absorbing elements in scientific and technical applications due to its extreme confinement, multiband absorption and polarization insensitivity. 展开更多
关键词 in is on of Extreme Light Concentration and high absorption of the Double Cylindrical Microcavities been Figure
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The High Energy Region of the Absorption Edge of a-Si:H, a Theoretical Study—III
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作者 Salwan Kamal Jamil Al-Ani Abdullah Ibrahim Subhi Saeed Al-Rawi 《Materials Sciences and Applications》 2012年第8期562-565,共4页
In this paper we try to give a reasonable account for the origin of the experimental optical energy gap Eo of a-Si:H deduced from the plot due to Cody ( vs. E). Using a realistic model density of states diagram for a-... In this paper we try to give a reasonable account for the origin of the experimental optical energy gap Eo of a-Si:H deduced from the plot due to Cody ( vs. E). Using a realistic model density of states diagram for a-Si:H and the constant dipole matrix element assumption, and a reasonable definition of the real optical energy gap EG, a new theoretical equation for ε2(E) was derived. The plot of the square root of this function as a function of the photon energy E for appropriate fitting parameters gives a straight line fit in the energy region of significance extrapolating to the energy axis at a value similar to the experimental optical gap but about 0.1 eV lower than the theoretical optical gap EG proposed in our paper. We conclude that the experimental optical gap Eo does not necessarily coincide with any optical transition threshold in the density of states diagram of a-Si:H. 展开更多
关键词 high Energy absorption EDGE
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Energy Absorption of Pultruded Glass-Graphite/Epoxy Hybrid Composites under High Strain-Rate Induced Transverse Tension
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作者 Damian Stoddard Suman Babu Ukyam +1 位作者 R. Mantena Prabhakar Arunachalam Rajendran 《Open Journal of Composite Materials》 2018年第2期43-53,共11页
This paper focuses on the dynamic tensile response of glass-graphite/epoxy composites illustrating improvement in energy absorption through hybridization. The dynamic response and energy absorption characteristics of ... This paper focuses on the dynamic tensile response of glass-graphite/epoxy composites illustrating improvement in energy absorption through hybridization. The dynamic response and energy absorption characteristics of pultruded hybrid combinations of glass and graphite fibers in an epoxy matrix subjected to induced transverse tension at high strain-rate in a modified Split Hopkinson Pressure Bar (SHPB) apparatus, are presented. Transverse tensile strength was determined by diametral compression of disc samples (Brazilian indirect tensile test method). Diametral crack initiation and strain to failure were monitored with a Shimadzu HPV-2 high-speed video camera at a recording speed of 500,000 fps and Digital Image Correlation (DIC). Adequate measures were taken to ensure that initiation of specimen failure occurred at the exact center of the disc specimen, and propagated through the diameter along the compressive loading axis, for the induced transverse tension tests to be valid. A study of the strength and specific energy absorption demonstrates the benefits of hybridization. Under induced transverse tensile loading condition, the pure glass/epoxy (GL60) exhibited higher strength than pure graphite/epoxy (GR60). Pure graphite/epoxy (GR60) has higher specific energy absorption capacity than pure glass/epoxy (GL60) in transverse tension. Among all hybrids, GR30 has the highest specific energy absorption under transverse tension. Overall, hybrid GL48, with 48% low-cost glass fibers in the inner core and 12% high-cost graphite fibers in outer shell, was found to exhibit better performance under induced transverse tension at high strain-rates, showing the benefits of hybridization. 展开更多
关键词 Pultruded Composites HYBRIDS high STRAIN-RATE SHPB Dynamic Energy absorption BRAZILIAN Disc Indirect Tensile Test
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Intestinal Absorption of Berberine and 8-Hydroxy Dihydroberberine and Their Effects on Sugar Absorption in Rat Small Intestine 被引量:6
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作者 魏世超 董苏 +1 位作者 徐丽君 张晨宇 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第2期186-189,共4页
The intestinal absorption ofberberine (Ber) and its structural modified compound 8-hydroxy dihydroberberine (Hdber) was compared, and their effects on the intestinal absorption of sugar by per- fusion experiment w... The intestinal absorption ofberberine (Ber) and its structural modified compound 8-hydroxy dihydroberberine (Hdber) was compared, and their effects on the intestinal absorption of sugar by per- fusion experiment were investigated in order to reveal the mechanism of low dose and high activity of Hdber in the treatment of hyperglycemia. The absorption of Hdber and Ber in rat small intestine was measured by in situ perfusion. High performance liquid chromatography (HPLC) was used to determine the concentrations of Hdber and Ber. In situ perfusion method was also used to study the effects of Hdber and Ber on sugar intestinal absorption. Glucose oxidase method and UV spectrophotometry were applied to examine the concentrations of glucose and sucrose in the perfusion fluid. The results showed that the absorption rate of Ber in the small intestine was lower than I0%, but that of Hdber was larger than 70%. Both Hdber and Ber inhibited the absorption of glucose and sucrose at the doses of 10 and 20 ~tg/mL. However, Hdber presented stronger activity than Bet (P〈0.01). It is suggested that Hdber is ab- sorbed easily in rat small intestine and that its inhibitory effect on the absorption of sugar is better than Ber. 展开更多
关键词 BERBERINE 8-hydroxy dihydroberberine PERFUSION absorption high performance liquidchromatography SUGAR
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Absorption of ultrashort intense lasers in laser–solid interactions
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作者 盛政明 翁苏明 +4 位作者 於陆勒 王伟民 崔云千 陈民 张杰 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期52-65,共14页
With the advent of ultrashort high intensity laser pulses, laser absorption during the laser–solid interactions has received significant attention over the last two decades since it is related to a variety of applica... With the advent of ultrashort high intensity laser pulses, laser absorption during the laser–solid interactions has received significant attention over the last two decades since it is related to a variety of applications of high intensity lasers,including the hot electron production for fast ignition of fusion targets, table-top bright X-ray and gamma-ray sources,ion acceleration, compact neutron sources, and generally the creation of high energy density matters. Normally, some absorption mechanisms found for nanosecond long laser pulses also appear for ultrashort laser pulses. The peculiar aspects with ultrashort laser pulses are that their absorption depends significantly on the preplasma condition and the initial target structures. Meanwhile, relativistic nonlinearity and ponderomotive force associated with the laser pulses lead to new mechanisms or phenomena, which are usually not found with nanosecond long pulses. In this paper, we present an overview of the recent progress on the major absorption mechanisms in intense laser–solid interactions, where emphasis is paid to our related theory and simulation studies. 展开更多
关键词 laser absorption laser–solid interaction relativistic high intensity electron heating and acceleration
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Absorption of Curcumin Monophosphate in Rat Intestinal Circulation
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作者 Yu WANG Luyang DING Longru SUN 《Medicinal Plant》 CAS 2019年第1期66-68,73,共4页
[Objectives] This study aimed to study the absorption of curcumin monophosphate, a derivative of curcumin, in the small intestine of rats. [Methods] In situ recirculation perfusion technique was used to study the abso... [Objectives] This study aimed to study the absorption of curcumin monophosphate, a derivative of curcumin, in the small intestine of rats. [Methods] In situ recirculation perfusion technique was used to study the absorption of curcumin monophosphate in intestinal circulation of rats, and the content of curcumin monophosphate in intestinal circulation solution was determined by high-performance liquid chromatography/ultraviolet detector(HPLC/UV). [Results] The established HPLC/UV method has good specificity. Linear regression was conducted between the peak area of curcumin monophosphate(A) and the concentration of curcumin monophosphate(C). The established standard curve equation was y=30.07x+102.48(R^2=0.999 0), indicating that curcumin monophosphate has good linearity in the range of 1.25-100.00 μg/mL. After excluding the degradation of the drug and the loss of sampling, within the first 2 h of the experiment, the drug absorption in the small intestine of rat was 1.39 mg, accounting for 97.2% of the total drug absorption during the 5-h experimental period, and the absorption rate was 53.9%.[Conclusions] Curcumin monophosphate has a good absorption in the small intestine of rats. 展开更多
关键词 CURCUMIN MONOPHOSPHATE In SITU recirculation PERFUSION Small INTESTINE absorption high performance liquid chromatography
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Electromagnetic wave absorption properties of Ba(CoTi)_(x)Fe_(12-2x)O_(19)@BiFeO_(3)in hundreds of megahertz band
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作者 Zhi-Biao Xu Zhao-Hui Qi +4 位作者 Guo-Wu Wang Chang Liu Jing-Hao Cui Wen-Liang Li Tao Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期612-620,共9页
The high-performance electromagnetic(EM)wave absorption material Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)was prepared by solid-state reaction,and its EM wave absorption properties were deeply studied.The results reveale... The high-performance electromagnetic(EM)wave absorption material Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)was prepared by solid-state reaction,and its EM wave absorption properties were deeply studied.The results revealed that Ba(Co Ti)x Fe12-2x O19@Bi Fe O_(3)could obtain excellent absorption properties in hundreds of megahertz by adjusting the Co^(2+)-Ti^(4+)content.The best comprehensive property was obtained for x=1.2,where the optimal reflection loss(RL)value reaches-30.42 d B at about 600 MHz with thickness of 3.5 mm,and the corresponding effective absorption band covers the frequency range of 437 MHz-1 GHz.Moreover,the EM wave absorption mechanism was studied based on the simulation methods.The simulated results showed that the excellent EM wave absorption properties of Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)mainly originated from the internal loss caused by natural resonance,and the interface cancelation further improved the absorption properties and resulted in RL peaks. 展开更多
关键词 microwave absorption M-type ferrite high permeability impedance matching
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Post-noon ionospheric absorption observed by the imaging riometers at polar cusp/cap conjugate stations
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作者 刘瑞源 胡红桥 《Chinese Journal of Polar Science》 1999年第2期125-132,共8页
An example of post-noon ionospheric absorption observed by the imaging riometers at Ny-Alesund / Danmarkshavn in the arctic region and Zhongshan Station in Antarctic is presented. The post-noon absorption observed sim... An example of post-noon ionospheric absorption observed by the imaging riometers at Ny-Alesund / Danmarkshavn in the arctic region and Zhongshan Station in Antarctic is presented. The post-noon absorption observed simultaneously between the hemispherical stations was a spike-type with weak intensity (<1 dB) during the high solar wind dynamic pressure. The absorption spikes might be caused by precipitation of highrenergy electrons (30 - 300 keV) in the closed dayside magnetosphere. It should be noted that the precipitation region of the absorption spike associated with the steep pressure increase (~ 13 nPa) was localized and shifted equatorward. 展开更多
关键词 post-noon ionospheric absorption conjugate imaging riometer high solar wind dynamic pressure
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Properties of Sustainable High Strength Concrete with Waste Copper Slag
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作者 JAGAN Sivamani KARUPASAMY Narayanan +3 位作者 DHARMARAJ R THIYANESWARAN Periyasamy KARTHIKEYAN Selvarajan NAVANEETHAN Kumaravalasu Subramaniam 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第4期815-822,共8页
The present work investigates copper slag as a substitute for river sand in high-strength concrete.The concrete mixtures were manufactured with 10%,30%,50%,70%,and 100%of copper slag to evaluate the mechanical and dur... The present work investigates copper slag as a substitute for river sand in high-strength concrete.The concrete mixtures were manufactured with 10%,30%,50%,70%,and 100%of copper slag to evaluate the mechanical and durability properties.The experimental results indicate that replacing copper slag above 50%affects the performance characteristics of the concrete due to its high angularity and lower water absorption characteristics.The strength of concrete with 50%copper slag is improved by 5.6%,whereas the strength of concrete with 100%copper slag is reduced by 2.75%at 28 days.However,increased curing to 90days improves the strength of the former by 7.16%and reduces the latter by only 0.23%.The water absorption,porosity,and rapid chloride penetration of the concrete mixtures with 100%copper slag are increased by 10.44%,13.20%,and 19.56%compared to control concrete.Micro-structural investigations through SEM infer higher replacement of copper results in higher void formation due to its reduced water absorption. 展开更多
关键词 copper slag high strength concrete STRENGTH water absorption POROSITY
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燃煤锅炉温度场与高温腐蚀气氛场同步在线检测装置开发及应用 被引量:1
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作者 王建荣 程银雪 +6 位作者 李龙 郭古青 田亚莉 孙小聪 周月婷 李传亮 邱选兵 《电力科技与环保》 2024年第2期116-124,共9页
燃煤锅炉主燃区燃烧场的经济性、安全性和环保性对于智慧电厂建设具有重要意义。其中,水冷壁近壁面高温腐蚀H_(2)S和CO气体浓度的实时在线监测尤为重要。为实现燃煤锅炉主燃区温度场和高温腐蚀气氛场的同步测量,基于红外热成像原理,采用... 燃煤锅炉主燃区燃烧场的经济性、安全性和环保性对于智慧电厂建设具有重要意义。其中,水冷壁近壁面高温腐蚀H_(2)S和CO气体浓度的实时在线监测尤为重要。为实现燃煤锅炉主燃区温度场和高温腐蚀气氛场的同步测量,基于红外热成像原理,采用Optris-PI1M小型红外热成像仪,基于LabVIEW温度实时采集应用软件,在炉膛的观察口对主燃区温度场进行连续监测。以低成本1.5μm附近的通信波段激光器作为测量高温腐蚀气体H_(2)S和CO的激光光源,并结合波长调制光谱技术和频分复用技术,以实现H_(2)S和CO气体浓度的同步检测。线性度实验表明,其线性拟合相关系数为0.9995。将研制的同步检测仪器对某300 MW四角切圆燃煤锅炉的主燃区的温度场和气氛场进行了现场应用试验。现场测试结果表明,锅炉主燃区温度主要分布范围在1300~1400℃,最高温度达到了1500℃;同时得到了锅炉主燃区的H_(2)S和CO浓度分布,H_(2)S浓度在12~125 mg/m^(3)的范围内波动,而CO浓度主要分布在10%~20%之间,最高可达22%;炉内H_(2)S和CO的浓度呈正相关,氧气浓度保持在1%以下,由于厌氧燃烧会导致两种气体的含量增加,从而造成对水冷壁近壁面的高温腐蚀。 展开更多
关键词 燃煤锅炉 高温腐蚀 红外热成像 激光吸收光谱 在线监测
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高声强双层穿孔结构的吸声计算
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作者 俞悟周 贺银芝 +1 位作者 姜在秀 孙浩钧 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第9期1464-1468,共5页
对高声强下不同的穿孔结构非线性声阻抗模型进行比较,分析入射声压对穿孔吸声结构声阻抗的影响,并提出双层穿孔结构的改进传递矩阵法。不同声阻抗模型的实验和计算结果表明,入射声压级小于140 dB时,Park模型和Maa模型的计算结果与实验... 对高声强下不同的穿孔结构非线性声阻抗模型进行比较,分析入射声压对穿孔吸声结构声阻抗的影响,并提出双层穿孔结构的改进传递矩阵法。不同声阻抗模型的实验和计算结果表明,入射声压级小于140 dB时,Park模型和Maa模型的计算结果与实验数据吻合良好;入射声压级为140~150 dB时,Laly模型的计算结果更接近实验结果。对于高声强下的双层及多层穿孔结构,在所提出的改进传递矩阵法中,根据传递矩阵计算得到各层板表面声压级,每层穿孔的声阻抗根据声压级和穿孔参数进行计算,进而得到总声阻抗。结果表明,入射声压级为120~150 dB时,双层穿孔结构的改进传递矩阵法计算结果与实验数据吻合良好。 展开更多
关键词 降噪 吸声 双层穿孔结构 高声强 非线性声阻抗
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悬滴微萃取-高分辨连续光源石墨炉原子吸收光谱法测定高纯石墨中的超痕量金
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作者 肖芳 张田园 +3 位作者 张丽萍 刘璐 毛香菊 倪文山 《岩矿测试》 CAS CSCD 北大核心 2024年第5期734-743,共10页
准确测定高纯石墨中的超痕量金,难点是如何在最大程度地减少样品前处理过程中器皿、试剂、材料、环境及设备所引入的二次污染的前提下,实现对样品溶液中超痕量金(0.1~1ng/mL)的有效分离和高倍富集。本文建立了铂皿中灰化、酸解、磷酸三... 准确测定高纯石墨中的超痕量金,难点是如何在最大程度地减少样品前处理过程中器皿、试剂、材料、环境及设备所引入的二次污染的前提下,实现对样品溶液中超痕量金(0.1~1ng/mL)的有效分离和高倍富集。本文建立了铂皿中灰化、酸解、磷酸三丁酯悬滴微萃取的方法用于高纯石墨中超痕量金分析。首先于铂皿中高温灼烧除去样品中的固定碳,然后采用氢氟酸-王水-高氯酸将灰分消解完全制备成样品溶液,再以微升级磷酸三丁酯悬滴作为萃取剂,分离富集样品溶液中的金,最后采用高分辨连续光源石墨炉原子吸收光谱法(GFAAS)对悬滴中的金进行测定。实验结果表明,使用2.5μL磷酸三丁酯悬滴(氯仿体积为20%)作为萃取剂,在10%盐酸介质的样品溶液中萃取金2min,对金的富集倍数可达283倍。在实验条件下,金的质量浓度在0.1~2.0ng/mL范围内与其吸光度呈良好的线性关系,相关系数r为0.999,检出限为0.11ng/g,样品溶液中一定量的共存元素(如钠、镁、铝)对金的测定无干扰。按照实验方法测定5个高纯石墨实际样品中的金含量,测定结果的相对标准偏差(RSD,n=6)为1.5%~4.9%,加标回收率为94.9%~105.3%。 展开更多
关键词 高纯石墨 悬滴微萃取 磷酸三丁酯 石墨炉原子吸收光谱法 超痕量
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光甘草定烟酰胺纳米乳的制剂评价与透皮吸收
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作者 赵海燕 陆金玲 +2 位作者 鲁妍 黄雨洁 王少兵 《中南民族大学学报(自然科学版)》 CAS 2024年第4期468-473,共6页
为提高光甘草定和烟酰胺的透皮吸收性能,利用两种高能乳化法制备了纳米乳(HPH-NE和HSSU-NE),对其形态、粒径、Zeta电位、稳定性和皮肤渗透性能进行了评价与考察.结果表明:两种纳米乳颗粒均为规则球形,未见聚集现象,平均粒径分别为51.60... 为提高光甘草定和烟酰胺的透皮吸收性能,利用两种高能乳化法制备了纳米乳(HPH-NE和HSSU-NE),对其形态、粒径、Zeta电位、稳定性和皮肤渗透性能进行了评价与考察.结果表明:两种纳米乳颗粒均为规则球形,未见聚集现象,平均粒径分别为51.60 nm和42.98 nm,Zeta电位分别为-50.44 mV和-68.50 mV,并且在离心、4℃和20℃以及加速试验条件下均具有较好的稳定性,两种方法制成的纳米乳相对普通乳液具有更好的皮肤渗透性能,光甘草定的平均渗透速率提高3~5倍,烟酰胺的平均渗透率提高1.6~2.6倍,为光甘草定的纳米制剂以及化妆品应用研究奠定了坚实基础. 展开更多
关键词 纳米乳 高压均质法 高速剪切超声法 光甘草定 烟酰胺 稳定性 透皮吸收
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高频燃烧红外吸收法测定铜铅锌多金属矿中的碳、硫
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作者 王琳 王楠 《中国无机分析化学》 CAS 北大核心 2024年第11期1563-1568,共6页
铜铅锌多金属矿中的碳、硫元素对矿产开采、钢铁冶炼及环境保护等方面有着重要的影响,对碳、硫的准确、快速定量检测至关重要,但未见有对铜铅锌多金属矿中的碳、硫同时测定的研究。将铜铅锌多金属矿中碳、硫含量科学分为C1、C2、S1、S2... 铜铅锌多金属矿中的碳、硫元素对矿产开采、钢铁冶炼及环境保护等方面有着重要的影响,对碳、硫的准确、快速定量检测至关重要,但未见有对铜铅锌多金属矿中的碳、硫同时测定的研究。将铜铅锌多金属矿中碳、硫含量科学分为C1、C2、S1、S2四段,并分别对样品称样量、助熔剂加入比例及种类等因素进行探究,建立了高频燃烧红外吸收法测定铜铅锌多金属矿中的碳、硫的方法,并通过标准物质验证了方法的准确度、精密度与再现性。结果表明,C1、C2、S1、S2称样量分别为0.200 0、0.100 0、0.100 0、0.100 0 g,助熔剂组合方式为Fe+W=(0.6000+0.6000)、(0.6000+0.6000)、(0.9000+0.6000)、(0.6000+0.600 0) g为最佳实验条件。C1、C2、S1、S2曲线的相关系数分别为0.999 4、0.995 9、0.999 9、0.998 9,测定结果的相对标准偏差(RSD,n=11)分别为1.3%、1.5%、1.3%、1.3%,使用3种不同型号的红外碳硫仪进行对比实验,相对标准偏差(RSD,n=11)为0.56%~6.5%。结果均显示,方法准确、可靠,满足铜铅锌多金属矿中碳、硫的同时、准确快速定量检测的要求。 展开更多
关键词 铜铅锌多金属矿 高频燃烧红外吸收光谱法
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