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新时代乡镇林业发展面临的困境及对策
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作者 栾盼盼 《中文科技期刊数据库(全文版)农业科学》 2024年第1期0024-0027,共4页
随着国家经济和社会发展步入新时期,在美丽乡村建设理念不断深入背景下,乡镇林业发展也面临着新的挑战,相关部门对乡镇林业发展的重视程度和对资源的支持程度也在不断提高。然而,随着社会经济的高速发展,林业公共利益和社会性矛盾日益凸... 随着国家经济和社会发展步入新时期,在美丽乡村建设理念不断深入背景下,乡镇林业发展也面临着新的挑战,相关部门对乡镇林业发展的重视程度和对资源的支持程度也在不断提高。然而,随着社会经济的高速发展,林业公共利益和社会性矛盾日益凸显,同时,受规模与土地使用权等因素的影响,使得乡镇林业发展受到了限制。基于此,本文对新时代乡镇林业发展面临的困境及对策进行了研究,首先阐述了加强乡镇林业发展的必要性,然后对新时代乡镇林业发展面临的困境进行了分析,最后提出了乡镇林业发展的一些优化对策。 展开更多
关键词 新时代 乡镇林业 困境及对策
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亲水改性聚氨酯纳米纤维酶膜催化油水两相体系转糖苷反应
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作者 栾盼盼 张羽飞 +4 位作者 张松平 姜艳军 李鹏举 苏志国 高静 《过程工程学报》 CAS CSCD 北大核心 2014年第3期469-475,共7页
利用静电纺丝法制备含LiCl的聚氨酯(PU)纳米纤维,用牛血清白蛋白(BSA)对纤维亲水改性,于其上固定β-D-半乳糖苷酶,提高酶在油水两相介质中催化转糖苷反应的活力.结果表明,以PU浓度26%(ω)的电纺液制备的直径240~300 nm的PU纤维膜... 利用静电纺丝法制备含LiCl的聚氨酯(PU)纳米纤维,用牛血清白蛋白(BSA)对纤维亲水改性,于其上固定β-D-半乳糖苷酶,提高酶在油水两相介质中催化转糖苷反应的活力.结果表明,以PU浓度26%(ω)的电纺液制备的直径240~300 nm的PU纤维膜在LiCl辅助作用下吸附BSA高达222 mg/g,使纤维膜的水接触角由103.7o降至77.3o.改性PU膜固定化酶比活力为1.59 U/mg,而未改性PU膜仅为其79.2%.改性膜固定化酶55℃下的活力半衰期高达游离酶的14倍,在4℃下储存45 d活力仍保持80%,而游离酶活力仅剩余16.3%;改性膜固定化酶重复催化42次转糖苷反应活力仍能保持31%. 展开更多
关键词 静电纺丝 聚氨酯纳米纤维 半乳糖苷酶 油水两相 转糖苷反应 亲水改性
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Research on optical fiber magnetic field sensors based on multi-mode fiber and spherical structure 被引量:2
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作者 WANG Yan TONG Zheng-rong +3 位作者 ZHANG Wei-hua LUAN Pan-pan ZHAO Yue XUE U-fang 《Optoelectronics Letters》 EI 2017年第1期16-20,共5页
A magnetic field sensor with a magnetic fluid(MF)-coated intermodal interferometer is proposed and experimentally demonstrated. The interferometer is formed by sandwiching a segment of single mode fiber(SMF) between a... A magnetic field sensor with a magnetic fluid(MF)-coated intermodal interferometer is proposed and experimentally demonstrated. The interferometer is formed by sandwiching a segment of single mode fiber(SMF) between a segment of multi-mode fiber(MMF) and a spherical structure. It can be considered as a cascade of the traditional SMF-MMF-SMF structure and MMF-SMF-sphere structure. The transmission spectral characteristics change with the variation of applied magnetic field. The experimental results exhibit that the magnetic field sensitivities for wavelength and transmission loss are 0.047 nm/m T and 0.215 d B/m T for the interference dip around 1 535.36 nm. For the interference dip around 1548.41 nm,the sensitivities are 0.077 nm/m T and 0.243 d B/m T. Simultaneous measurement can be realized according to the different spectral responses. 展开更多
关键词 spherical interferometer coated cladding cascade matching detecting agglomeration coupler colloidal
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An optical fiber magnetic field sensor based on fiber spherical structure interferometer coated by magnetic fluid
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作者 徐丰田 栾盼盼 +1 位作者 贾科松 张爱玲 《Optoelectronics Letters》 EI 2015年第5期379-381,共3页
A novel magnetic field sensor based on optical fiber Mach-Zehnder interferometer(MZI) coated by magnetic fluid(MF) is proposed. The MZI consists of two spherical structures formed on standard single mode fiber(SMF). T... A novel magnetic field sensor based on optical fiber Mach-Zehnder interferometer(MZI) coated by magnetic fluid(MF) is proposed. The MZI consists of two spherical structures formed on standard single mode fiber(SMF). The interference wavelength and the power of the sensing structure are sensitive to the external refractive index(RI). Since RI of the MF is sensitive to the magnetic field, the magnetic field measurement can be realized by detecting the variation of the interference spectrum. Experimental results show that the wavelength and the power of interference dip both increase with the increase of magnetic field intensity. 展开更多
关键词 spherical interferometer coated cladding detecting refractive magnet grating realized etching
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