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Isolation and purification of carbazole contained in anthracene slag by extraction combined with medium pressure liquid chromatography 被引量:1
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作者 Zhihao Ma XianyongWei +5 位作者 Mingyao Zhou Guanghui Liu Fangjing Liu Zhongqiu Liu Xinyue Yu Zhimin Zong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第12期2925-2929,共5页
Ultrasonic-assisted extraction(UAE)combined with medium pressure liquid chromatography(MPLC)was designed for carbazole separation from anthracene slag(AS).The effects of liquid/solid ratio,temperature,and extraction t... Ultrasonic-assisted extraction(UAE)combined with medium pressure liquid chromatography(MPLC)was designed for carbazole separation from anthracene slag(AS).The effects of liquid/solid ratio,temperature,and extraction times on carbazole separation were investigated.When using CC14 and ethyl acetate as extraction solvents and combining with MPLC,carbazole recovery and purity are 75.1%and 95.4%,respectively.The mechanism for carbazole separation were presumed by examining intermolecular interactions such as N-H…π,π-π,and C-Cl…πinteractions.These results demonstrate that UAE/MPLC has a considerable potential as a green and promising strategy for separating and purifying carbazole and other chemicals from AS. 展开更多
关键词 Anthracene SLAG ULTRASONIC-ASSISTED EXTRACTION medium pressure liquid chromatography INTERMOLECULAR interactions
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P-wave velocity prediction in porous medium with liquid-pocket patchy saturation
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作者 Jiawei LIU Weitao SUN Jing BA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第11期1427-1440,共14页
It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical... It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical gas pockets were located at the center of a liquid saturated cube. For an extremely light and compressible inner gas, the physical properties can be approximated by a vacuum with White's model. The model successfully analyzes the dispersion phenomena of a P-wave velocity in gas-water- saturated rocks. In the case of liquid pocket saturation, e.g., an oil-pocket surrounded by a water saturated host matrix, the light fluid-pocket assumption is doubtful, and few works have been reported in White's framework. In this work, Poisson's ratio, the bulk modulus, and the effective density of a dual-liquid saturated medium are formulated for the heterogeneous porous rocks containing liquid-pockets. The analysis of the difference between the newly derived bulk modulus and that of White's model shows that the effects of liquid-pocket saturation do not disappear unless the porosity approaches zero. The inner pocket fluid can no longer be ignored. The improvements of the P-wave velocity predictions are illustrated with two examples taken from experiments, i.e., the P-wave velocity in the sandstone saturated by oil and brine and the P-wave velocity for heavy oils and stones at different temperatures. 展开更多
关键词 White's model porous medium P-wave dispersion liquid pocket
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Non-aerated liquid culture promotes shoot organogenesis in Eucalyptus globulus Labill 被引量:1
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作者 T.D.Salla C.dos S.Silva +2 位作者 K.L.de G.Machado L.V.Astarita E.R.Santarém 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期621-627,共7页
Eucalyptus is very recalcitrant to in vitro culture.In this research, an efficient shoot organogenesis system was developed using 60-day-old plants of Eucalyptus globulus grown in vitro and non-aerated liquid medium t... Eucalyptus is very recalcitrant to in vitro culture.In this research, an efficient shoot organogenesis system was developed using 60-day-old plants of Eucalyptus globulus grown in vitro and non-aerated liquid medium to improve shoot proliferation. Cultures were initiated with hypocotyls and leaf segments from plantlets cultivated on semisolid 1/2 MS modified medium supplemented with 4.44 μM 6-Benzyladenine(BA) and 16.1 μM 1-Naphthaleneacetic acid(NAA). Calli were transferred to shoot induction medium, with either 0.5 or 2.7 μM NAA. Shoot multiplication was carried out on 4.44 μM BA + 0.5 μM NAA medium, and semisolid and non-aerated liquid systems were compared for improving shoot proliferation.Rooting of adventitious shoots was evaluated on medium containing NAA or Indole-3-butyric acid-IBA(5 and16 μM). Callogenesis was obtained from both types of explants, although shoot formation was only obtained from leaf-derived calli. Shoot proliferation on 4.44 μM BA+0.5 μM NAA resulted in the most shoots/callus.Non-aerated liquid medium was more efficient in promoting shoot multiplication(53.5 shoots/callus) than was semisolid medium(28.5 shoots/callus). Levels of phenolic compounds were significantly reduced in the shoots cultivated in liquid medium. Efficient rooting(76%) was obtained using 16 μM IBA. 展开更多
关键词 Adventitious shoots CALLUS liquid medium MICROPROPAGATION Phenolic compounds ROOTING
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Darcy-Forchheimer flow of variable conductivity Jeffrey liquid with Cattaneo-Christov heat flux theory 被引量:1
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作者 M. A. MERAJ S.A. SHEHZAD +2 位作者 T. HAYAT F.M. ABBASI A. ALSAEDI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第4期557-566,共10页
The role of the Cattaneo-Christov heat flux theory in the two-dimensional laminar flow of the Jeffrey liquid is discussed with a vertical sheet. The salient feature in the energy equation is accounted due to the imple... The role of the Cattaneo-Christov heat flux theory in the two-dimensional laminar flow of the Jeffrey liquid is discussed with a vertical sheet. The salient feature in the energy equation is accounted due to the implementation of the Cattaneo-Christov heat flux. A liquid with variable thermal conductivity is considered in the Darcy-Forchheimer porous space. The mathematical expressions of momentum and energy are coupled due to the presence of mixed convection. A highly nonlinear coupled system of equations is tackled with the homotopic algorithm. The convergence of the homotopy expressions is calculated graphically and numerically. The solutions of the velocity and temperature are expressed for various values of the Deborah number, the ratio of the relaxation time to the retardation time, the porosity parameter, the mixed convective parameter, the Darcy-Forchheimer parameter, and the conductivity parameter. The results show that the velocity and temperature are higher in Fourier's law of heat conduction cases in comparison with the Cattaneo-Christov heat flux model. 展开更多
关键词 Darcy-Forchheimer porous medium variable conductivity Jeffrey liquid Cattaneo-Christov heat flux
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Study on Optimization of Culture Conditions for Wild Isaria cicadae Miquel Liquid Strain
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作者 Chunqin XIE Zheng CAO +2 位作者 Junmin FAN Junqi XU Jun JIA 《Medicinal Plant》 CAS 2018年第1期25-29,共5页
[Objectives] To study the effect of different culture conditions on the growth of wild I. cicadae Miq. liquid strain. [Methods]The I. cicadae Miq. strain was inoculated into the liquid culture medium with different ca... [Objectives] To study the effect of different culture conditions on the growth of wild I. cicadae Miq. liquid strain. [Methods]The I. cicadae Miq. strain was inoculated into the liquid culture medium with different carbon sources,nitrogen sources,micronutrients and p H,cultured in the constant temperature shaking incubator with rotating speed of 120 r/min at 19℃,and the mycelium pellet diameter,density and weight were compared between different treatments. [Results] The results showed that the optimum components of I. cicadae Miq.strain liquid included soluble starch,milk powder and vitamin B_(12),and the optimum p H was 5. 0-6. 0. [Conclusions] Soluble starch was the most suitable carbon source for the culture medium of I. cicadae Miq. liquid strain; milk powder was the most suitable nitrogen source for the culture medium of I. cicadae Miq. liquid strain; the most suitable p H was 5. 0-9. 0 for the mycelial growth of I. cicadae Miq.; the formula and mixture ratio of the optimum culture medium for the growth of liquid strain were determined. 展开更多
关键词 Wild Isaria cicadae Miquel liquid strain Culture medium
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扁蓿豆花粉萌发特性研究
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作者 钟华 向清源 +2 位作者 尚晓岚 朱慧森 李钰莹 《草地学报》 北大核心 2025年第6期1791-1799,共9页
本研究旨在优化扁蓿豆(Medicago ruthenica)花粉离体萌发的培养条件。通过单因素试验初步筛选出蔗糖、硼酸和氯化钙的最适浓度范围,并利用三因素两水平试验进一步优化培养条件,比较不同处理下花粉萌发率和花粉管生长长度。结果表明,培... 本研究旨在优化扁蓿豆(Medicago ruthenica)花粉离体萌发的培养条件。通过单因素试验初步筛选出蔗糖、硼酸和氯化钙的最适浓度范围,并利用三因素两水平试验进一步优化培养条件,比较不同处理下花粉萌发率和花粉管生长长度。结果表明,培养基组分、温度及采样时间等因素对花粉萌发有极显著影响。最优培养基组分为蔗糖(200 g·L^(-1))、硼酸(40 mg·L^(-1))和氯化钙(30 mg·L^(-1)),在此条件下,花粉萌发率达75.98%,花粉管长度为224.73μm。最佳培养时间为6 h,最适采样时间为中午12:00—13:00,且在黑暗条件下花粉萌发效果更好,最佳培养条件为25℃,最佳贮藏温度为4℃。本研究结果为扁蓿豆花粉生物学研究及育种实践提供了理论依据。 展开更多
关键词 扁蓿豆 离体萌发 液体培养基 培养条件
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Polyethylene Glycol as Support and Phase Transfer Catalyst in Aqueous Palladium-catalyzed Liquid-phase Synthesis
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作者 Xia, M Wang, YG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期941-942,共2页
Excellent yields and purity were obtained in the aqueous medium Suzuki, Sonogashira, Stille and Heck reactions using palladium (II) as catalyst in liquid phase synthesis. Polyethylene glycol (PEG) acted as soluble pol... Excellent yields and purity were obtained in the aqueous medium Suzuki, Sonogashira, Stille and Heck reactions using palladium (II) as catalyst in liquid phase synthesis. Polyethylene glycol (PEG) acted as soluble polymeric support and phase transfer catalyst as well. 展开更多
关键词 aqueous medium PALLADIUM-CATALYZED polyethylene glycol liquid-phase synthesis
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青稞条纹病原菌的接种方法优化和利用
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作者 侯璐 方世玉 +1 位作者 康胜华 龙有 《植物保护》 北大核心 2025年第3期276-281,共6页
条纹病是青藏高原青稞生产上的重要种传病害之一,带菌种子是青稞条纹病的唯一初侵染菌源,常采用三明治法幼芽接种病原菌,但其试验周期长和对青稞种子的侵染效率较低。为提高人工接种条纹病病原菌的侵染效率,本研究建立了液体培养条纹病... 条纹病是青藏高原青稞生产上的重要种传病害之一,带菌种子是青稞条纹病的唯一初侵染菌源,常采用三明治法幼芽接种病原菌,但其试验周期长和对青稞种子的侵染效率较低。为提高人工接种条纹病病原菌的侵染效率,本研究建立了液体培养条纹病病原菌菌丝体接种青稞种子的液体侵染接种方法,确定液体侵染法的最适接种条件。研究发现,从整个试验周期看,液体侵染法耗时为三明治法的42.9%~57.9%,从青稞种子与病原菌的共培养时间来看,液体侵染法耗时为三明治法的7.9%。缩短人工接种处理时间18.42 d,说明液体侵染法可作为室内接种鉴定青稞品种对条纹病抗性的有效方法。本研究采用液体侵染法对30份青稞种质资源进行抗病性鉴定,获得免疫性遗传资源材料3份、高抗类型材料5份、中抗类型材料8份、中度感病类型材料3份、高度感病类型材料11份。本研究采用液体侵染接种方法提高病原菌侵染率,缩短侵染处理时间,对改进青稞条纹病菌接种具有重要意义。 展开更多
关键词 青稞 条纹病 液体培养基 抗病性评价
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High Performance Liquid Chromatography Separation and Simultaneous Fluorometric Detection of Trace Amount of Polyamines in Cell Culture Media
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作者 王淳本 雷景迈 +1 位作者 柴锡禄 何善述 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1995年第2期125-128,共4页
A highly sensitive and precise method for the determination of the polyamines (including putrescine, spermidine and spermine) in cell culture media is described. The samples were concentrated by C18 column and the pol... A highly sensitive and precise method for the determination of the polyamines (including putrescine, spermidine and spermine) in cell culture media is described. The samples were concentrated by C18 column and the polyamines were converted to fluorometric derivatives with DNS-Cl. The polyamine derivatives were then completely separated by HPLC and determined by simultaneous fluorometric detection. The CV of intragroup and intergroup were 2. 49 %-4. 26% and 4. 29 %-5. 16 %, respectively. The rate of recovery was 103%- 99%. There was trace amount of polyamines detected by this method in the media of F12, 8900, RPMI1640, DMEM and M199 even without incubation with cells. So this method can be used for detecting the changes of polyamines in a medium before and after incubation with cells. It is helpful for the researches on the regulation of cell proliferation by polyamines. 展开更多
关键词 medium PUTRESCINE SPERMIDINE SPERMINE high performance liquid chromatography fluorospectrophotometry
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不同贮藏条件下滇山茶花粉萌发与花粉活力保存 被引量:2
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作者 李振勤 耿芳 +4 位作者 聂瑞敏 胡云冲 杨自云 王仲朗 陈龙清 《分子植物育种》 北大核心 2025年第4期1195-1201,共7页
采取合适的花粉储藏方式对保存花粉活力、提高杂交育种成功率非常关键,为探究不同培养时间、不同培养基配方对滇山茶花粉萌发的影响以及不同保存温度条件下滇山茶花粉生活力的差异,本研究以滇山茶及其品种‘梅红’、‘粉牡丹’、‘亮叶... 采取合适的花粉储藏方式对保存花粉活力、提高杂交育种成功率非常关键,为探究不同培养时间、不同培养基配方对滇山茶花粉萌发的影响以及不同保存温度条件下滇山茶花粉生活力的差异,本研究以滇山茶及其品种‘梅红’、‘粉牡丹’、‘亮叶银红’的花粉为试验材料开展研究。结果表明,滇山茶及其品种‘梅红’、‘粉牡丹’、‘亮叶银红’的花粉在配比为100 g/L蔗糖+200 mg/L硼酸的培养基上离体培养24 h时,花粉萌发率均达到最大值,分别为48.1%、44.4%、53.1%和50.5%;与4℃和常温保存相比,花粉在-20℃时保存90 d的活力最高,滇山茶及其品种‘梅红’、‘粉牡丹’、‘亮叶银红’分别达到40.0%、28.8%、32.9%和32.7%,而且相对于新鲜花粉的活力降幅最小;滇山茶及其品种‘梅红’、‘粉牡丹’、‘亮叶银红’在不同培养条件下,各品种之间的花粉生活力无显著性差异。本研究结果可采取合适储藏条件保存滇山茶花粉活力,为提高滇山茶杂交育种成功率提供一定的理论依据。 展开更多
关键词 滇山茶 花粉活力 离体萌发 花粉保存 液体培养基
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Feasibility Demonstrations of Liquid Turbine Power Generator Driven by Low Temperature Heats 被引量:2
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作者 Seiichi Deguchi Norifumi Isu +1 位作者 Hidenori Kato Saeko Miwa 《Journal of Power and Energy Engineering》 2016年第8期59-67,共9页
Lower temperature waste heats less than 373 K have strong potentials to supply additional energies because of their enormous quantities and ubiquity. Accordingly, reinforcement of power generations harvesting low temp... Lower temperature waste heats less than 373 K have strong potentials to supply additional energies because of their enormous quantities and ubiquity. Accordingly, reinforcement of power generations harvesting low temperature heats is one of the urgent tasks for the current generation in order to accomplish energy sustainability in the coming decades. In this study, a liquid turbine power generator driven by lower temperature heats below 373 K was proposed in the aim of expanding selectable options for harvesting low temperature waste heats less than 373 K. The proposing system was so simply that it was mainly composed of a liquid turbine, a liquid container with a biphasic medium of water and an underlying water-insoluble low-boiling-point medium in a liquid phase, a heating section for vaporization of the liquid and a cooling section for entropy discharge outside the system. Assumed power generating steps via the proposing liquid turbine power generator were as follows: step 1: the underlying low-boiling-point medium in a liquid phase was vaporized, step 2: the surfacing vapor bubbles of low-boiling-point medium accompanied the biphasic medium in their wakes, step 3: such high momentum flux by step 2 rotated the liquid turbine (i.e. power generation), step 4: the surfacing low-boiling-point medium vapor was gradually condensed into droplets, step 5: the low-boiling-point medium droplets were submerged to the underlying medium in a liquid phase. Experiments with a prototype liquid turbine power generator proved power generations in accordance with the assumed steps at a little higher than ordinary temperature. Increasing output voltage could be obtained with an increase in the cooling temperature among tested ranging from 294 to 296 K in contrast to normal thermal engines. Further improvements of the direct current voltage from the proposing liquid turbine power generator can be expected by means of far more vigorous multiphase flow induced by adding solid powders and theoretical optimizations of heat and mass transfers. 展开更多
关键词 liquid Turbine Power Generator Low Temperature Heats Recovery Phase Changes Biphasic medium Energy Harvesting Technology
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煤岩介质对液氮汽化速率影响的实验教学设计
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作者 雷柏伟 徐志兵 +1 位作者 吴兵 王政 《实验室科学》 2025年第5期12-17,共6页
实验教学可以加强学生对液氮传热机理和液氮汽化规律的研究。通过设计搭建液氮沸腾换热汽化实验平台,基于重量连续监测来分析标准尺寸煤岩介质浸入液氮内的沸腾换热过程以及其对液氮汽化速率的影响。将实验结果与理论计算模型进行对比验... 实验教学可以加强学生对液氮传热机理和液氮汽化规律的研究。通过设计搭建液氮沸腾换热汽化实验平台,基于重量连续监测来分析标准尺寸煤岩介质浸入液氮内的沸腾换热过程以及其对液氮汽化速率的影响。将实验结果与理论计算模型进行对比验证,结果表明:液氮沸腾换热汽化实验可以准确反映不同煤岩介质浸入液氮后汽化速率变化情况。通过开展实验教学,能够清晰直观地展示实验的完整过程,增加学生感性认识,加深对所学知识的理解,通过将理论知识与实践相结合的方法培养学生分析问题和解决问题的能力,获得了良好的实验教学效果。 展开更多
关键词 液氮 汽化速率 煤岩介质 实验教学
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响应面法优化添加太子参的云芝液体发酵培养基及发酵产物分析 被引量:1
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作者 赵生月 张余 +2 位作者 姜春玲 刘盛荣 叶祖云 《宁德师范学院学报(自然科学版)》 2025年第1期64-72,共9页
为有效利用太子参资源,拓宽其应用领域,以太子参根须作为重要原料,利用响应面法优化云芝液体发酵培养基,并进行发酵产物活性成分分析。结果显示:以生物量为评价指标,优化的培养基为太子参21g·L^(-1)、蛋白胨11 g·L^(-1)、蔗糖... 为有效利用太子参资源,拓宽其应用领域,以太子参根须作为重要原料,利用响应面法优化云芝液体发酵培养基,并进行发酵产物活性成分分析。结果显示:以生物量为评价指标,优化的培养基为太子参21g·L^(-1)、蛋白胨11 g·L^(-1)、蔗糖15.81 g·L^(-1)、KH_(2)PO_(4)1.2 g·L^(-1)。菌丝体生物量、胞内三帖和胞内多糖含量,优化培养基均最高,分别为5.69、15.24×10^(-3)和0.58 g·L^(-1),比对照分别提高87.17%、85.63%和81.25%,比PDB培养基分别提高378.15%、361.82%和544.44%;发酵液的胞外多糖含量,以优化培养基发酵的为最高,达0.25 g·L^(-1),比对照提高127.27%,比PDB提高257.14%。菌丝生长和活性产物合成的结果表明:太子参根须是云芝深层发酵的良好底物,可促进云芝菌丝生长和活性产物合成。 展开更多
关键词 太子参 云芝 液体发酵 培养基优化
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粉被虫草液体静置发酵产N^(6)-(2-羟乙基)腺苷培养基优化 被引量:1
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作者 廖兴刚 孟泽彬 +1 位作者 贺凤姣 文庭池 《分子植物育种》 北大核心 2025年第9期3046-3051,共6页
为了获得粉被虫草中高产N^(6)-(2-羟乙基)腺苷(HEA)的培养基,采用液体静置发酵的方式,以菌丝体HEA的产量为指标,HPLC法检测含量,采用单因素试验法研究培养基中8种碳源、8种氮源和8种无机盐对粉被虫草产HEA的影响;用正交试验筛选最佳培... 为了获得粉被虫草中高产N^(6)-(2-羟乙基)腺苷(HEA)的培养基,采用液体静置发酵的方式,以菌丝体HEA的产量为指标,HPLC法检测含量,采用单因素试验法研究培养基中8种碳源、8种氮源和8种无机盐对粉被虫草产HEA的影响;用正交试验筛选最佳培养基组合。结果显示,蛋白胨、果糖和ZnSO4分别是粉被虫草产HEA的最适氮源、最适碳源和最适无机盐;其最佳培养基组合为蛋白胨15 g/L、果糖40 g/L、硫酸锌0.5 g/L,此时的HEA产量为(92.311±2.209)mg/L,是目前报道粉被虫草中的最高产量。本研究将为粉被虫草规模生产HEA提供试验参考。 展开更多
关键词 粉被虫草 N^(6)-(2-羟乙基)腺苷 液体静置发酵 培养基
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紫荆花粉萌发液体培养基的筛选及培养条件优化
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作者 杨延红 陈文双 +4 位作者 姜君军 马晶晶 李慧敏 裴宝智 姜倩倩 《种子》 北大核心 2025年第7期234-239,245,共7页
为了筛选紫荆花粉(Cercis chinensis)离体萌发最适液体培养基组分,以紫荆花粉为试验材料,采用液体培养法探究蔗糖、硼酸、硝酸钙、不同培养温度及时间对紫荆花粉萌发的影响。结果表明,花粉离体萌发适宜培养基组分为:20%蔗糖+200 mg/L硼... 为了筛选紫荆花粉(Cercis chinensis)离体萌发最适液体培养基组分,以紫荆花粉为试验材料,采用液体培养法探究蔗糖、硼酸、硝酸钙、不同培养温度及时间对紫荆花粉萌发的影响。结果表明,花粉离体萌发适宜培养基组分为:20%蔗糖+200 mg/L硼酸+100 mg/L硝酸钙,此时花粉萌发率达86.43%,花粉管长度为175.37μm;适宜的离体培养时间为5 h,培养温度为25℃。温度是关键影响因子,温度不适宜会导致保护酶活性降低,破坏活性氧代谢平衡,加剧膜脂过氧化,阻碍花粉萌发与花粉管生长。 展开更多
关键词 紫荆 液体培养基 花粉萌发 花粉管长度 培养温度
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基于周向Lamb波的钢管杆积存固液态检测
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作者 王驰 岳贤强 +3 位作者 马君鹏 柳伟续 薛珂瑀 张鹏飞 《声学技术》 北大核心 2025年第4期554-564,共11页
电力钢管杆塔作为输电线路的重要组成部分,被广泛应用于电网基础设施建设中,是保障工业与民生的重要电力设备之一。针对钢管杆塔受到积存固液态介质载荷作用,比如常见的积水或积冰,更易发生电化学腐蚀,出现镀锌层减薄、局部锈蚀、内壁... 电力钢管杆塔作为输电线路的重要组成部分,被广泛应用于电网基础设施建设中,是保障工业与民生的重要电力设备之一。针对钢管杆塔受到积存固液态介质载荷作用,比如常见的积水或积冰,更易发生电化学腐蚀,出现镀锌层减薄、局部锈蚀、内壁减薄和表面压溃等缺陷,损害钢管杆塔结构健康。为此,以积水介质为例,开展了基于周向Lamb波的电力钢管杆塔积水检测研究,提出了一种基于小波包分解、主成分分析和奇异值分解的钢管杆塔积水检测方法。最后,研究了不同激励频率范围、斜探头入射角度及周向Lamb波指向性对积水检测的影响,并通过钢管杆塔积水检测实验验证了文中所提方法的可行性和有效性。 展开更多
关键词 电力钢管杆塔 积存固液态介质 小波包分解 主成分分析
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等离子体射流在渐扩型充液室中扩展特性的数值模拟
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作者 贾舒翔 余永刚 《兵工学报》 北大核心 2025年第4期357-366,共10页
等离子体射流在液体工质中扩展时存在影响燃烧过程稳定的正反馈机制,限制了其进一步实际应用化。为探寻等离子体射流在整装式液体工质中的扩展特性,建立等离子体射流与液体工质相互作用的二维轴对称非稳态数学物理模型,并进行模型验证... 等离子体射流在液体工质中扩展时存在影响燃烧过程稳定的正反馈机制,限制了其进一步实际应用化。为探寻等离子体射流在整装式液体工质中的扩展特性,建立等离子体射流与液体工质相互作用的二维轴对称非稳态数学物理模型,并进行模型验证。设计4级渐扩型充液室结构,开展等离子体射流在液体药LP1846模拟工质中扩展特性的数值分析,获得等离子体射流场中压力、速度和温度等特性参数的时空分布规律。研究结果表明:4级渐扩充液室结构可以利用阶梯的诱导作用,增强等离子体射流在充液室径向扩展能力和等离子体射流头部高压高温区径向影响范围,从而控制等离子体射流轴向扩展速度和脉动性;黏度、密度大的液体药LP1846模拟工质,结合渐扩充液室结构可以减缓等离子体射流的轴向扩展速度,可以有效抑制Kelvin-Helmholtz不稳定性和Taylor不稳定性,有利于增强等离子体射流扩展的稳定性;近喷口处由于膨胀-压缩波交替产生导致近场压力、温度存在波动性。 展开更多
关键词 等离子体射流 渐扩边界 液体工质 KELVIN-HELMHOLTZ不稳定性 Taylor空腔
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秀珍菇液体菌种培养基及培养条件优化
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作者 黄显斌 蔡为明 +2 位作者 陈青 金群力 冯伟林 《北方园艺》 北大核心 2025年第3期105-113,共9页
以秀珍菇的“金秀漳州”菌种为试材,采用单因素比较和响应面设计方法,研究了秀珍菇液体培养基碳氮源以及其他培养条件对秀珍菇液体菌种的菌丝体生物量以及菌丝球大小的影响,以期为秀珍菇液体菌种的制备和扩大培养提供参考依据。结果表明... 以秀珍菇的“金秀漳州”菌种为试材,采用单因素比较和响应面设计方法,研究了秀珍菇液体培养基碳氮源以及其他培养条件对秀珍菇液体菌种的菌丝体生物量以及菌丝球大小的影响,以期为秀珍菇液体菌种的制备和扩大培养提供参考依据。结果表明:最佳碳源是葡萄糖,最佳氮源是蛋白胨,最佳配方是葡萄糖21.050 g·L^(-1),蛋白胨5.304 g·L^(-1),KH_(2)PO_(4)0.524 g·L^(-1),MgSO_(4)0.942 g·L^(-1)。最佳培养条件是温度25℃,恒温振荡摇床转速150 r·min^(-1),培养天数11 d。 展开更多
关键词 秀珍菇 液体菌种 摇瓶优化 培养基优化
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响应面法优化液态发酵培养基和发酵条件促进间型脉胞菌OK菌丝体蛋白生产
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作者 韩思雨 戴意强 +5 位作者 王喆 何子茵 王道营 孙玲 印伯星 夏秀东 《生物加工过程》 2025年第5期555-567,共13页
为了快速高效地获得间型脉胞菌菌丝体蛋白,本研究通过单因素实验和响应面法对液态发酵间型脉胞菌的培养基组成成分和培养条件进行优化。结果表明:间型脉胞菌OK菌丝体蛋白的最佳培养基成分为蔗糖34 g/L,酵母提取物5 g/L、MgSO_(4)1.5 g/... 为了快速高效地获得间型脉胞菌菌丝体蛋白,本研究通过单因素实验和响应面法对液态发酵间型脉胞菌的培养基组成成分和培养条件进行优化。结果表明:间型脉胞菌OK菌丝体蛋白的最佳培养基成分为蔗糖34 g/L,酵母提取物5 g/L、MgSO_(4)1.5 g/L、维生素B_(2)0.1 g/L;最佳发酵条件为发酵初始p H 6、发酵时间5 d、发酵温度28℃、发酵转速180 r/min。在此条件下的菌丝体蛋白质产量达3.64 g/L,比基础培养基的蛋白质产量(1.10 g/L)提高了230.91%。 展开更多
关键词 间型脉胞菌 液态发酵 培养基优化 培养条件优化 响应面优化
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垂穗披碱草中黄酮类化合物的分离及其对高脂血症斑马鱼脂质代谢的影响 被引量:1
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作者 童莹莹 初明 +3 位作者 党军 黄海辉 马成俊 李刚 《烟台大学学报(自然科学与工程版)》 2025年第1期64-73,共10页
旨在从垂穗披碱草(Elymus nutans Griseb.)中分离黄酮类化合物,并研究其对高脂饮食诱导的高脂血症斑马鱼脂质代谢的影响。采用中高压液相色谱结合二维液相色谱等方法进行分离纯化,利用核磁共振波谱(NMR)、质谱(MS)等技术鉴定化合物结构... 旨在从垂穗披碱草(Elymus nutans Griseb.)中分离黄酮类化合物,并研究其对高脂饮食诱导的高脂血症斑马鱼脂质代谢的影响。采用中高压液相色谱结合二维液相色谱等方法进行分离纯化,利用核磁共振波谱(NMR)、质谱(MS)等技术鉴定化合物结构;建立高脂饮食诱导的斑马鱼幼鱼高脂血症模型,化合物持续喂养5 d后,检测各组斑马鱼幼鱼的存活率、体重、体长、BMI的变化;油红O染色、HE染色分别观察脂质积累情况和组织病理学变化;生化试剂盒测定总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-c)、高密度脂蛋白胆固醇(HDL-c);实时荧光定量PCR(qRT PCR)检测脂质代谢相关mRNA的表达变化。从垂穗披碱草中分离得到2个黄酮类同分异构体化合物,分别鉴定为夏佛塔苷和异夏佛塔苷。夏佛塔苷和异夏佛塔苷能明显改善高脂饮食诱导的斑马鱼肝脏脂质积累和肝脏组织细胞排列松散及空泡化现象;与模型组相比,两种化合物均能降低TG、TC、LDL-c并提升HDL-c水平,异夏佛塔苷改善效果更为显著。其作用机制可能与下调脂肪酸合成基因SREBF1和FASN的表达、提高胆固醇代谢相关基因RORα的表达有关。 展开更多
关键词 中高压液相色谱 夏佛塔苷 异夏佛塔苷 斑马鱼 高脂血症
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