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Light Simplified Foxtail Millet Cultivation Technique Adopting Furrow Sowing beside Plastic Film Covering Micro-ridges
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作者 夏雪岩 程汝宏 +6 位作者 宋世佳 刘猛 赵宇 任晓利 刘斐 南春梅 李顺国 《Agricultural Science & Technology》 CAS 2016年第4期869-871,876,共4页
In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and tim... In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and time saving, Millet Research Institute of Hebei Academy of Agriculture and Forestry Sciences integrated furrow sowing beside plastic film covering micro-ridges, simplified cultivation and mechanized production, forming the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges. This study introduced the technique points of the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges, including preparation before sowing,sowing, attached agricultural machines, field management, harvest and residual film recovery. 展开更多
关键词 Foxtail millet Integration of furrow sowing beside plastic film covering micro-ridges fertilization and simplified cultivation SIMPLIFICATION
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Simulation Experiment of Air Temperature Variation in Multi-film Covering at Night
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作者 Chuankun ZHANG Yunhua NIU +4 位作者 Zigao JIAO Chongqi WANG Min WEI Kun XU Ning YANG 《Agricultural Biotechnology》 CAS 2019年第5期102-105,共4页
In order to provide theoretical basis and data support for improving the production mode of covering,this study investigated the nighttime air temperature formed by multiple layers of films with tunnel sheds and small... In order to provide theoretical basis and data support for improving the production mode of covering,this study investigated the nighttime air temperature formed by multiple layers of films with tunnel sheds and small tunnel sheds as trial subjects.The experiment was carried out in four tunnel sheds with 0 or 2 small tunnel sheds covered by 0,1,2 and 3 layers of films,respectively in Jinan,Shandong Province in winter of 2018.The nighttime air temperatures of tunnel sheds and small tunnel sheds formed by 1,2,3 and 4 layers of plastic film were measured and analyzed to simulate the temperature environment of early-spring season.The results showed that there were little differences between the nighttime air temperatures inside the tunnel sheds which was installed 0-3-layer small tunnel sheds inside,and there were uncertainty in the values of the air temperatures inside and outside the tunnel sheds;and the nighttime temperature conditions were constantly improved with the number of plastic film layers increasing under the conditions of this study.The analysis indicated that the mechanism of raising the temperature surrounded by plastic film was not only due to its own thermal parameter (thermal conductivity).MATLAB fitting analysis results showed that the increment of nighttime temperature in multi-film coverings became smaller with the number of film layers increasing.In this study,the number of layers in multi-film covering should not exceed 5 layers. 展开更多
关键词 Multi-film covering TUNNEL SHED Small TUNNEL SHED NIGHTTIME air temperature Simulation Thermal parameter
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Effects of film-stalk spaced dual mulching system on corn growth and yield
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作者 CAO Jinjun SUN Yaqi +7 位作者 PENG Shuili LI Wanxing HE Xiaobing LI Xiaoxia LI Dan JIN Kunpeng YANG Yi LIU Yongzhong 《Journal of Arid Land》 SCIE CSCD 2024年第12期1714-1729,共16页
Film-stalk spaced dual mulching is a new type of cultivation measure that is increasingly highlighted in semi-arid areas in China.Despite its potential,there is limited understanding of how different mulching material... Film-stalk spaced dual mulching is a new type of cultivation measure that is increasingly highlighted in semi-arid areas in China.Despite its potential,there is limited understanding of how different mulching materials affect both soil quality and crop yield in these areas.To address this gap,we conducted a two-year(2020-2021)field experiment in central China to explore the yield-enhancing mechanisms and assess the impact of various mulching materials on soil and corn yield.The experiment comprised six treatments,i.e.,plastic film-whole stalk spaced mulching in fall(PSF),plastic film-whole stalk spaced mulching in spring(PSS),black and silver plastic film-whole stalk spaced mulching in spring(BPSS),biodegradable film-whole stalk spaced mulching in spring(BSS),liquid film-whole stalk spaced mulching in spring(LSS),and non-mulching cultivation(CK).Results revealed that BPSS demonstrated the most significant yield increase,surpassing CK by a notable 10.0%and other mulching treatments by 2.4%-5.9%.The efficacy of BPSS lied in its provision of favorable hydrothermal conditions for corn cultivation,particularly during hot season.Its cooling effect facilitated the establishment of optimal temperature conditions relative to transparent mulching,leading to higher root growth indices(e.g.,length and surface area),as well as higher leaf photosynthetic rate and dry matter accumulation per plant.Additionally,BPSS maintained higher average soil moisture content within 0-100 cm depth compared with biodegradable mulching and liquid mulching.As a result,BPSS increased activities of urease,catalase,and alkaline phosphatase,as well as the diversity and abundance of soil bacteria and fungi in the rhizosphere zone of corn,facilitating nutrient accessibility by the plant.These findings suggest that selecting appropriate mulching materials is crucial for optimizing corn production in drought-prone areas,highlighting the potential of BPSS cultivation. 展开更多
关键词 film-stalk spaced dual mulching black plastic film cover CORN yield conservational tillage system
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Drug-eluting fully covered self-expanding metal stent for dissolution of bile duct stones in vitro 被引量:9
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作者 Chao Huang Xiao-Bo Cai +3 位作者 Li-Li Guo Xiao-Sheng Qi Qiang Gao Xin-Jian Wan 《World Journal of Gastroenterology》 SCIE CAS 2019年第26期3370-3379,共10页
BACKGROUND The treatment of difficult common bile duct stones(CBDS)remains a big challenge around the world.Biliary stenting is a widely accepted rescue method in patients with failed stone extraction under endoscopic... BACKGROUND The treatment of difficult common bile duct stones(CBDS)remains a big challenge around the world.Biliary stenting is a widely accepted rescue method in patients with failed stone extraction under endoscopic retrograde cholangiopancreatography.Fully covered self-expanding metal stent(FCSEMS)has gained increasing attention in the management of difficult CBDS.AIM To manufacture a drug-eluting FCSEMS,which can achieve controlled release of stone-dissolving agents and speed up the dissolution of CBDS.METHODS Customized covered nitinol stents were adopted.Sodium cholate(SC)and disodium ethylene diamine tetraacetic acid(EDTA disodium,EDTA for short)were used as stone-dissolving agents.Three different types of drug-eluting stents were manufactured by dip coating(Stent I),coaxial electrospinning(Stent II),and dip coating combined with electrospinning(Stent III),respectively.The drugrelease behavior and stone-dissolving efficacy of these stents were evaluated in vitro to sort out the best manufacturing method.And the selected stonedissolving stents were further put into porcine CBD to evaluate their biosecurity.RESULTS Stent I and Stent II had obvious burst release of drugs in the first 5 d while Stent III presented controlled and sustainable drug release for 30 d.In still buffer,the final stone mass-loss rate of each group was 5.19%±0.69%for naked FCSEMS,20.37%±2.13%for Stent I,24.57%±1.45%for Stent II,and 33.72%±0.67%for Stent III.In flowing bile,the final stone mass-loss rate of each group was 5.87%±0.25%for naked FCSEMS,6.36%±0.48%for Stent I,6.38%±0.37%for Stent II,and 8.15%±0.27%for Stent III.Stent III caused the most stone mass-loss no matter in still buffer or in flowing bile,which was significantly higher than those of other groups(P<0.05).In vivo,Stent III made no difference from naked FCSEMS in serological analysis(P>0.05)and histopathological examination(P>0.05).CONCLUSION The novel SC and EDTA-eluting FCSEMS is efficient in diminishing CBDS in vitro.When conventional endoscopic techniques fail to remove difficult CBDS,SC and EDTA-eluting FCSEMS implantation may be considered a promising alternative. 展开更多
关键词 Common BILE duct stone DRUG-ELUTING STENT Fully coverED self-expanding metal STENT Electrospinning NANOFIBER film
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Formation of epitaxial Tl_2Ba_2Ca_2Cu_3O_(10) superconducting films by dc-magnetron sputtering and triple post-annealing method 被引量:5
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作者 解伟 王培 +9 位作者 季鲁 葛德永 杜佳男 高晓昕 刘欣 宋凤斌 胡磊 张旭 何明 赵新杰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期697-702,共6页
For obtaining pure phase T12Ba2Ca2Cu3O10 (T1-2223) films with good superconducting properties, the growth technique is improved by dc magnetron sputtering and a triple post-annealing process. The triple post-anneali... For obtaining pure phase T12Ba2Ca2Cu3O10 (T1-2223) films with good superconducting properties, the growth technique is improved by dc magnetron sputtering and a triple post-annealing process. The triple post-annealing process comprises annealing twice in argon and once in oxygen at different temperatures. In the first low-temperature annealing phase in argon, T12Ba2CaCu2O8 (T1-2212) is obtained to effectively minimize evaporation in the next step. With the increase of temperature in the second annealing stage in argon, the previously prepared T1-2212 inter-phase is converted into T1-2223 phase. An additional annealing in oxygen is also adopted to improve the properties of T1-2223 films, each containing an optimal oxygen content value. The results of X-ray diffraction (XRD) θ-2θ scans, 09 scans and rotational φ scans show that each of the T1-2223 films has a high phase purity and an epitaxial structure. Smooth films are observed by scanning electron microscopy (SEM). The critical temperatures Tc of the films are measured to be about 120 K and the critical current densities Jc can reach 4.0 MA/cm2 at 77 K at self field. 展开更多
关键词 T1-2223 superconducting films POST-ANNEALING critical temperature critical current density
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Transparent and anti-fogging AlPO_(4)-5 films constructed by oblique oriented nano-flake crystals 被引量:1
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作者 Fei Tong Jie Gong +2 位作者 Liang Yu Ming Li Lixiong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第4期332-340,共9页
In the present work,transparent and anti-fogging AlPO_(4)-5 films were prepared on glass substrates using a novel developed process.The process entails a simple in-situ sol–gel followed by vapor phase transport.The i... In the present work,transparent and anti-fogging AlPO_(4)-5 films were prepared on glass substrates using a novel developed process.The process entails a simple in-situ sol–gel followed by vapor phase transport.The in-situ sol–gel process was implemented by coating the precursor sols for the synthesis of AlPO4-5 on the glass substrates successively using the spin-coating method.The films and powders scribed from the films were characterized by X-Ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scanning electron microscope(SEM),atomic force microscope(AFM),X-ray photoelectron spectroscopy and transmission electron microscope(TEM).The unique films were composed of oblique oriented nanoflake AlPO_(4)-5 crystals with the thickness of about 20 nm.The formation of nano-flake crystals can be ascribed to the high concentration of the precursors,resulting in the formation of a supersaturation system.The obtained films showed high antifogging performance due to the superhydrophilicity with a water contact angle of lower than 1.0°.The silicone oil contact angle was also low about 8.2°.In addition,heteroatom-substituted AlPO_(4)-5 films showing different colors can be obtained easily by simply adding transition metal ions in the phosphate acid solution during the preparation that can extend the application of the method for different coating demand. 展开更多
关键词 AlPO_(4)-5 thin film Oriented film TRANSPARENT SUPERHYDROPHILICITY ANTI-FOGGING
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The EVA plastic film for V-process and steel castings by V-process in China 被引量:1
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作者 Ye Shengping Wang Lei Liu Dehan 《China Foundry》 SCIE CAS 2008年第2期77-81,共5页
EVA plastic film is the key material for V-process. Through decades of research, special EVA film for V-process has been produced. The film has adequate elongation; its maximum is about 800% in longitudinal direction ... EVA plastic film is the key material for V-process. Through decades of research, special EVA film for V-process has been produced. The film has adequate elongation; its maximum is about 800% in longitudinal direction and 750% in transversal direction. The single width of the film is 2.8 m and the double width is 5.6 m, which is the widest sheet film for V-process in China. Sheets with different thickness ranging from the thickest 0.35 mm to the thinnest 0.08 mm can meet different demands in China. The film can be used not only for V-process of iron castings, but also for the manganese steel railway frog, steel rocking support and side frame castings for train and the steel bridge box for engine truck. 展开更多
关键词 V - Process EVA plastic film steel castings
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Enhancing superconductivity of ultrathin YBa2Cu3O7-δ films by capping non-superconducting oxides 被引量:1
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作者 Hai Bo Tianshuang Ren +2 位作者 Zheng Chen Meng Zhang Yanwu Xie 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期403-407,共5页
In this study, we have explored the ways to fabricate and optimize high-quality ultrathin YBa2 Cu3 O7-δ(YBCO) films grown on single-crystal(001) SrTiO3 substrates. Nearly atomic-flat YBCO films are obtained by pulsed... In this study, we have explored the ways to fabricate and optimize high-quality ultrathin YBa2 Cu3 O7-δ(YBCO) films grown on single-crystal(001) SrTiO3 substrates. Nearly atomic-flat YBCO films are obtained by pulsed laser deposition.Our result shows that the termination of SrTiO3 has only a negligible effect on the properties of YBCO. In contrast, we found that capping a non-superconducting oxide layer can generally enhance the superconductivity of YBCO. PrBa2 Cu3 O7,La2 CuO4, LaMnO3, SrTiO3, and LaAlO3 have been examined as capping layers, and the minimum thickness of superconducting YBCO with capping is ~ 2 unit cells–3 unit cells. This result might be useful in constructing good-performance YBCO-based field effect devices. 展开更多
关键词 YBa2Cu3O7-δ(YBCO) SUPERCONDUCTIVITY OXIDES film
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Synthesis of New Multibranch Chromophores with Strong Light-emitting in Solution and in PMMA Film 被引量:1
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作者 XiaoMeiWANG TianSheYANG +3 位作者 PingYANG QinFenSHI WanLiJANG HongDeXIE 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1135-1138,共4页
Three new chromophores with triphenylamine as molecular focal point bearing one, two, or three 4-(n-butyloxystyryl) group(s) at the periphery respectively, (named as T1, T2, and T3) have been synthesized and character... Three new chromophores with triphenylamine as molecular focal point bearing one, two, or three 4-(n-butyloxystyryl) group(s) at the periphery respectively, (named as T1, T2, and T3) have been synthesized and characterized. It is interesting to find that the fluorescence quantum yield increases from T1 (0.489), to T3 (0.535), and to T2 (0.628) in cyclohexane, meanwhile the lifetime for T3 is shorter than T1 and T2, which is an important characteristic for applications in light emitting diode. Also PMMA (polymethyl methacrylate) film doped with T3 gives stronger fluorescence than T1, and T2. Cyclic voltammetry showed that T3 exhibited lowest oxidation potential of 0.52 V vs SCE, suggesting its better hole-transport property. 展开更多
关键词 Trans-4-(4'-n-butyloxy-styryl) triphenylamine trans-4 4- di (4'-n- butyloxy- styryl)- triphenylamine trans-4 4 4-tris(4'-n-butyloxystyryl)triphenylamine photo- luminescence film.
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MICROSTRUCTURAL CHANGE OF YSZ-SUPPORTED YBaCuO SUPPERCONDUCTING FILM BY PROTON BEAM BOMBARDMENTS
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作者 王广厚 罗成林 +7 位作者 潘国强 颜石乾 韩民 杨森祖 李元 吉争鸣 孙志坚 吴培亨 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第3期129-136,共8页
Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion... Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion from tetragonal to orthorhombic phases, reduction of nonsuperconducting phase and preferential rearrangement of crystal grains are all favorable to the improvement of superconductivity in the YBaCuO film supported by YSZ substrate by proton beam bombardment. 展开更多
关键词 YBACUO superconducting film PROTON irradiation Scanning electron MICROSCOPE X - Ray diffraction Conversion of PHASES
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Growth and transport features of electron-doped superconductor Pr_(1-x)LaCe_xCuO_(4-δ) thin films
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作者 高丽娟 金魁 +7 位作者 赵力 吴彬新 李位勇 朱北沂 曹立新 许波 邱详冈 赵柏儒 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期2054-2057,共4页
Tt-phase electron-doped superconductor Pr1-xLaCexCuO4-δ(PLCCO) thin films are successfully prepared on SrTiOs (100) substrates by using the dc magnetron sputtering method. It is found that the films each have a h... Tt-phase electron-doped superconductor Pr1-xLaCexCuO4-δ(PLCCO) thin films are successfully prepared on SrTiOs (100) substrates by using the dc magnetron sputtering method. It is found that the films each have a highly oriented structure along the c-axis. For optimally doped films with x ≈ 0.10, the superconducting transition temperature Tc is 25.5 K, which is similar to that of a single crystal. The quadratic temperature dependence of the resistivity is observed when T 〉 To, which can be attributed to the two-dimensional Fermi liquid behaviour. Besides, the optimal conditions for preparing the T1-phase PLCCO thin films are also discussed in detail. 展开更多
关键词 electron-doped cuprate Pr1-xLaCexCuO4-δ thin film magnetron sputtering
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Preparation of c-Axis Oriented LiNb_(1-x) Ta_xO_3 Films on Si(111) Substrates by a Modified Sol-gel Process
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作者 QIANG Liang sheng FU Hong gang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期255-257,共3页
In this work, we succeeded in the preparation of LiNb 1- x Ta x O 3 films on Si(111) substrates by means of sol gel process, and the usual sol gel process for the preparation of LiNbO 3 and LiTaO 3 films on Si substra... In this work, we succeeded in the preparation of LiNb 1- x Ta x O 3 films on Si(111) substrates by means of sol gel process, and the usual sol gel process for the preparation of LiNbO 3 and LiTaO 3 films on Si substrates was improved by adding a 33% aqueous solution of CH 3CH 2OH to the mixed sols of LiNb(OCH 2CH 3) 6 and LiTa(OCH 2CH 3) 6 . The crystallization behavior of LiNb 1- x Ta x O 3 films on Si(111) substrates has been studied. Highly c axis oriented LiNb 1- x Ta x O 3 films have been obtained within the tantalum composition range of \{0< x <0 33\}. Some factors such as the hydrogen termination of the silicon surface, the RTP annealing process that provides the unidirectional heat flow and the preheating temperature are discussed to analyze the crystallization of the c axis oriented films. 展开更多
关键词 LiNb 1- x Ta x O 3 film Crystallization behavior Si substrate Sol gel
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High T_c HoBa_2Cu_3O_(7-δ) Thin Films Deposited on (100) Y_2O_3Stabilized ZrO_2 Substrates by Sputtering
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作者 彭正顺 杨秉川 +1 位作者 王小平 赵忠贤 《Rare Metals》 SCIE EI CAS CSCD 1995年第2期123-126,共4页
Thin films of superconductors HoBa_2Cu_3O_(7-δ)(HBCO) were prepared by DC-sputtering technique. The epi-taxial growth was controlled by the ratio of the oxygen pressure and Ar pressure (O_2/Ar) , the subetrate temper... Thin films of superconductors HoBa_2Cu_3O_(7-δ)(HBCO) were prepared by DC-sputtering technique. The epi-taxial growth was controlled by the ratio of the oxygen pressure and Ar pressure (O_2/Ar) , the subetrate temperature T_s and the distance of the target to subetrate. Thin films deposited under the optimum conditions (Po_2/P_(Ar)= 1:2 ; T_s=730℃) show a critical temlierature clase to 87K and a transition width less than 1K. X-raydiffraction analysis shows that the films are highiy c-axis oriented. Auger electron spectroscopy depth profilingdemonstrates Ho diffusion into the Zr(Y)O_2 subetrate owing to the Ho subetitution for Y. 展开更多
关键词 Superconducting material HoBa_2Cu_3O_(7-δ) Thin film
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IONIC CONDUCTIVITY OF POLY (β-ALKOXYCARBONYLETHYLMETHYLSILOXANE)-LiClO_4 CROSSLINKED FILMS
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作者 李永军 吴留仁 +1 位作者 方世璧 江英彦 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第2期127-132,共6页
Poly (β-carboxyethylmethylsiloxane)-LiClO_4 and poly (β-alkoxylethylmethylsiloxane)-LiClO_4 crosslinked fllms have been prepared. The ionic conductivity of the films depends on the polymer species, concentration of ... Poly (β-carboxyethylmethylsiloxane)-LiClO_4 and poly (β-alkoxylethylmethylsiloxane)-LiClO_4 crosslinked fllms have been prepared. The ionic conductivity of the films depends on the polymer species, concentration of lithium perchlorate, temperature and content of crosslinking agent. The effect of high polar organic solvent 1, 4-butyrolactone on the ionic conductivity and mechanical properties of poly (β-carhoxyethylmethylsiloxane )-LiClO_4 system was also investignied. 展开更多
关键词 Ionic conductivity: Poly(β-alkoxycarbonylethylmethylsiloxane)- Lithium Complex 1 4-butyrolactone Crosslinked film.
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Water and nitrogen transport characteristics of single-line interference infiltration under film hole irrigation with muddy water and fertilizer
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作者 JIANG Ruirui FEI Liangjun KANG Shouxuan 《排灌机械工程学报》 CSCD 北大核心 2022年第5期496-503,共8页
Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation ... Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation with muddy water and fertilizer.The relationship between the single-line interference infiltration parameters,the sand content,the wetting front movement distances,and the sand content were all established.The model of the cumulative infiltration volume of per unit film pore area,the vertical and horizontal wetting front movement distance of the free surface,and the wetting front movement distance of the interference center with sand content and infiltration time were proposed.Reveal the law of the change of soil water content and the distribution of NO_(3)^(-)-N content based on different muddy water sand content.The results indicate that at the same infiltration time,as the muddy water sand content increases,the cumulative infiltration volume per unit pore area decreases.The infiltration index of the free infiltration and the single-line interference vary little when the sand content increases,mainly are around 0.64 and 0.58.The relationship between infiltration parameters a,b and the sand content is linear function.At the same location,the more the sand content,the smaller the wetting front movement distance in free surface and the single-line interference surface,the less the NO_(3)^(-)-N content. 展开更多
关键词 film hole irrigation single-line interference infiltration muddy water FERTILIZER sand content NO_(3)^(-)-N content
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Preparation of Y_(1-x)Ho_xBa_2Cu_3O_(7-δ) Superconductive Thin Films
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作者 彭正顺 杨秉川 +3 位作者 王小平 石东奇 华志强 赵忠贤 《Rare Metals》 SCIE EI CAS CSCD 1995年第2期106-109,共4页
Y_(1-x)Ho_xBa_2Cu_3O_(7-δ)(0<x<1) sinsle crystal thin films oriented with the caxis perpendicular to the sur-face were grown by DC magnetron sputtering technique. Target was pieced together with half of YBa_2Cu... Y_(1-x)Ho_xBa_2Cu_3O_(7-δ)(0<x<1) sinsle crystal thin films oriented with the caxis perpendicular to the sur-face were grown by DC magnetron sputtering technique. Target was pieced together with half of YBa_2Cu_3O_(7-δ)(YBCO) and half of HoBa_2Cu_3O_(7-δ)(HBCO) superconducting materials. As the distance between HBCO targetmaterial and substrate is varied , the Ho content in material is changed respectively. When the content of Ho is0. 7 (atom ratio) , the T_c>83K. 展开更多
关键词 e : Y_(1-x)Ho_xBa_2Cu_3O_(7-δ) SUPERCONDUCTOR Thin film DC magnetronsputtering High critical temperature
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Hydrocarbon-Generating Model of the Area Covered With Volcanic Rock
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作者 Guo Zhanqian Zhang Yuwei 《Global Geology》 2000年第2期142-155,共14页
The distribution of Oil & gas fields shows their close relationship with the most active tectonic regions. This is not a coincidence but having a scientific reasons. The crustal active regions, refer to the places... The distribution of Oil & gas fields shows their close relationship with the most active tectonic regions. This is not a coincidence but having a scientific reasons. The crustal active regions, refer to the places where the active natural earthquake, volcanic activities, underground water happened, and the areas of the leaking Off of natural gas to the surface of the crust. The magma of volcanic activities brings the organic "kitchen range body" hydrocarbon - generating model and inorganic genetic hydrocarbon to the regions covered by volcanic rock. Underground water brings a catalytic hydrocarbon generating model for organic matter, and the leaking - off of H2 and CO2 contributes a synthetic hydrocarbon - generating model. Volcanic activities bring the assemblage of Source, Reservoir and Seal formed by the sediments and magma the sedimentary basins, and the hydrocarbon - generating system with a "water - volcano" binary structure is formed. All these conditions are favorable and excellent for the formation of oil & gas fields. The distribution of AInerican oil & gas fields have very close relationship with the mines of Fe, Mn, Cr, Mo, W and V, deposits of Zn, Cu, V, Pb, Al and Hg, and the deposits of fluorite, sulfur, potassium salt, phosphate and halite, and the distribution of sulfate - chloride of river water. The reason why few oil & gas fields discovered in the regions covered by volcanic rock in western America maybe because of the view of "inconsistency between petroleum and volcano". Further more, It’s very difficult to carry out a geophysical exploration in such kinds of regions. This paper examined a few hydrocarbon - generating models (systems) mentioned above and came up with some flesh ideas on the exploration in the areas covered with volcanic rocks. 展开更多
关键词 Active structural system Oil & gas fields HYDROCARBON - generating model Regions coverED with VOLCANIC rock in western AMERICA
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The transverse laser induced thermoelectric voltages in step flow growth (1-x)Pb(Mg_(1/3)Nb_(2/3))O_(3-x)PbTiO_3 thin films
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作者 尚杰 张辉 +2 位作者 李勇 曹明刚 张鹏翔 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期452-457,共6页
This paper reports that the transverse laser induced thermoelectric voltages (LITV) axe observed for the first time in the step flow growth (1- x)PD(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT, x = 0.20, 0.33, 0.50) thin fi... This paper reports that the transverse laser induced thermoelectric voltages (LITV) axe observed for the first time in the step flow growth (1- x)PD(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT, x = 0.20, 0.33, 0.50) thin films deposited on vicinal-cut strontium titanate single crystal substrates. Because lead magnesium niobate-lead titanate is a solid solution of lead magnesium niobate (PMN) and lead titanate (PT), there are two types of signals. One is wide with a time response of a microsecond, and the other superimposed with the wide signal is narrow with a time response of a nanosecond. The transverse LITV signals depend on the ratio of PMN to PT drastically. Under the irradiation of 28-ns pulsed KrF excimer laser with the 248-nm wavelength, the largest induced voltage is observed in the 0.50Pb(Mg1/3Nb2/3)O3-0.50 PbTiO3 films. Moreover, the effects of film thickness, substrates, and tilt angles of substrates are also investigated. 展开更多
关键词 laser induced thermoelectric voltage (1- x)PD(Mg1/3Nb2/3)O3-xPbTiO3 films anisotropic Seebeck effect
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2M-2覆膜机的设计与试验 被引量:1
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作者 何金伟 杜元鹏 《拖拉机与农用运输车》 2024年第1期68-71,共4页
随着农用机械与机具的普及,对应覆膜播种机和覆膜移栽机的机具越来越多,覆膜机的作业质量直接影响覆膜播种机出苗率和覆膜移栽机秧苗的成活率。通过对覆膜机各关键部件的设计研究,针对覆膜过程中影响覆膜质量的关键问题进行设计计算,确... 随着农用机械与机具的普及,对应覆膜播种机和覆膜移栽机的机具越来越多,覆膜机的作业质量直接影响覆膜播种机出苗率和覆膜移栽机秧苗的成活率。通过对覆膜机各关键部件的设计研究,针对覆膜过程中影响覆膜质量的关键问题进行设计计算,确定覆膜机关键参数,并进行现场试验,铺膜效果高于国标要求,解决了麦间套种铺膜作业有机难用的难题。 展开更多
关键词 覆膜机 铺膜 试验
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基于CERES-Rice模型的覆膜旱作稻田增温效应模拟 被引量:6
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作者 马雯雯 金欣欣 +5 位作者 石建初 宁松瑞 李森 陶玥玥 张亚男 左强 《农业工程学报》 EI CAS CSCD 北大核心 2015年第9期215-222,共8页
水稻覆膜旱作技术具有显著的节水、增温、防污和减排效应,是节水稻作技术体系的重要措施之一,将CERES-Rice模型用于覆膜旱作条件时,必须首先解决覆膜增温效应的准确模拟问题。该文拟应用热量传输理论及目前旱地作物生产系统中采用的覆... 水稻覆膜旱作技术具有显著的节水、增温、防污和减排效应,是节水稻作技术体系的重要措施之一,将CERES-Rice模型用于覆膜旱作条件时,必须首先解决覆膜增温效应的准确模拟问题。该文拟应用热量传输理论及目前旱地作物生产系统中采用的覆膜增温效应模拟方法,来模拟水稻覆膜旱作生产体系中的增温效应,从而为完善CERES-Rice模型并使其能用于覆膜旱作水稻的生长模拟奠定基础。参数调校与模型检验验证通过2013、2014年在湖北房县开展的2 a水稻覆膜旱作田间试验来进行,共涉及淹水(对照)、覆膜湿润栽培和覆膜旱作共3个水分处理,分别对2个生长季、2个覆膜处理地表5 cm及地下10、20 cm处温度的变化过程进行了模拟,结果表明:经过参数调校后,所建立的覆膜增温模型可较好地模拟覆膜稻田地表和剖面上土壤温度的变化规律,地表5 cm处土壤温度模拟值与实测值的均方根差、相对均方根差分别低于1.8℃和10%,相关系数在0.89以上(P<0.01);尽管地下10、20 cm处的模拟误差稍大,也基本可满足要求,相应的均方根误差<3.2℃,相对均方根差<15%,相关系数>0.65(P<0.01)。 展开更多
关键词 模型 土壤 覆膜 水稻覆膜旱作 增温效应 模拟 CERES-Rice
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