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DIS创新教具在初中物理实验循证教学中的融合实践——以“测量滑轮组机械效率”改进创新为例
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作者 景明明 曲曙光 潘书朋 《中学物理》 2026年第2期57-60,共4页
聚焦初中物理循证教学,以“测量滑轮组机械效率”为例,深入探讨传感器与数字化工具融合的实践应用,详细阐述了将力传感器与数字化显示及处理设备相结合,不断改进实验装置的过程,包括实验器材的创新设计、实验数据的数字化呈现.通过这项... 聚焦初中物理循证教学,以“测量滑轮组机械效率”为例,深入探讨传感器与数字化工具融合的实践应用,详细阐述了将力传感器与数字化显示及处理设备相结合,不断改进实验装置的过程,包括实验器材的创新设计、实验数据的数字化呈现.通过这项融合实践,不仅提升了实验数据的准确性、实时性与可操作性,还激发了学生对物理实验的兴趣,培养了学生的科学探究与数据处理能力,为初中物理实验循证教学提供了一定的参考与借鉴. 展开更多
关键词 diS创新教具 初中物理实验 循证教学 融合实践
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Camptothecin and 10-Hydroxycamptothecin Accumulate Differentially Under Specific Developmental Control in Camptotheca acuminata 被引量:11
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作者 祖元刚 唐中华 +1 位作者 于景华 赵春建 《Acta Botanica Sinica》 CSCD 2003年第4期494-499,共6页
Camptotheca acuminata Decaisne is a tree unique to China, producing terpenoid indole alkaloid (TIA), camptothecin (CPT), and 10-hydroxycamptothecin (HCPT), which possesses strong anti-cancer bioactivity. The dynamics ... Camptotheca acuminata Decaisne is a tree unique to China, producing terpenoid indole alkaloid (TIA), camptothecin (CPT), and 10-hydroxycamptothecin (HCPT), which possesses strong anti-cancer bioactivity. The dynamics of HCPT and CPT during seed maturation, seed germination, postgerminative development and daily growth were measured by High Performance Liquid Chromatography (HPLC). This article provides some evidence for presenting the theory that each characteristic of HCPT and CPT accumulation is under developmental regulation and then attempt to elucidate the metabolic relationships between them. HCPT accumulates particularly in young tissues and organs and is relatively unstable, while the distribution of CPT is more ubiquitous and stable. Their different distribution properties suggest that HCPT and CPT are differentially regulated and play distinct roles:during development. 展开更多
关键词 Camptotheca acuminata CAMPTOTHECIN 10-HYDROXYCAMPTOTHECIN CONTROL DEVELOPMENT
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Different Responses of Camptothecin and 10-Hydroxycamptothecin to Heat Shock in Camptotheca acuminata Seedlings 被引量:7
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作者 祖元刚 唐中华 +3 位作者 于景华 刘士刚 王微 郭晓瑞 《Acta Botanica Sinica》 CSCD 2003年第7期809-814,共6页
Plants interact with their environment by producing a diverse array of secondary metabolites, one of which is alkaloid. In this study, alkaloids, including camptothecin (CPT) and 10-hydroxycamptothecin (HCPT), malondi... Plants interact with their environment by producing a diverse array of secondary metabolites, one of which is alkaloid. In this study, alkaloids, including camptothecin (CPT) and 10-hydroxycamptothecin (HCPT), malondialdehyde (MDA) and chlorophyll contents were measured during heat shock in seedlings of Camptotheca acuminata Decaisne unique to China. Responses of different tissues, including young leaves, old leaves, buds and barks, to heat shock were examined in alkaloid changes. CPT and HCPT concentrations reached their peak values separately at 38 degreesC and 40 degreesC, which were below the lethal heat-shock temperature indicated by MDA and chlorophyll, and their great changes took place in young leaves. These results indicated that CPT and HCPT were involved in the C acuminata resistance against heat shock from its environment. Furthermore, plant rigidly observed the cost-benefit principle and mobilized and allocated limited alkaloid sources to young and reproductive tissues preferentially. In addition, HCPT displayed well-regulated changes during incubation at sublethal temperature, and this indicated that HCPT might play a more positively defensive role in enhancement of plant thermotolerance than CPT does. 展开更多
关键词 Camptotheca acuminata CAMPTOTHECIN 10-HYDROXYCAMPTOTHECIN RESPONSE heat shock
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Nitrate reductase activity and its diurnal variation rhythm for Camptotheca acuminata seedlings 被引量:1
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作者 孙世芹 阎秀峰 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期167-170,共4页
Nitrate reductase activity (NRA) in different plant organs and leaves in different positions of Camptotheca acuminata seedlings was determined by an In vivo assay, the diurnal variation rhythm of NRA in leaves of diff... Nitrate reductase activity (NRA) in different plant organs and leaves in different positions of Camptotheca acuminata seedlings was determined by an In vivo assay, the diurnal variation rhythm of NRA in leaves of different positions was observed,and the correlations between leaf NRA, leaf area and lamina mass per unit area (LMA) were also examined. The results showed that NRA in the leaf was significantly highest, compared with that in other organs such as roots, stems and leaves. In this experiment, the 10 leaves were selected from the apex to the base of the seedlings in order. The different NRA occurred obviously in leaves of different positions of C. acuminata seedlings from the apex to the base, and NRA was higher in the 4th-6th leaves.The diurnal change rhythm of leaf NRA showed a one peak curve, and maximum NRA value appeared at about midday (at 12:30 or so). No obvious correlations between NRA and leaf area or lamina mass per unit area were observed. This study offered scientific foundation for the further research on nitrogen metabolism of C. acuminata. 展开更多
关键词 Camptotheca acuminata Nitrate reductase activity diurnal variation
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The effects of different nitrogen sources on camptothecin content and related gene expression in Camptotheca acuminata seedlings 被引量:3
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作者 Xiaode Wang Sainan Bian +9 位作者 Pengjie Chang Ninghang Wang Lingjuan Xuan Mingru Zhang Bin Dong Chao Zhang Jiasheng Wu Yeqing Ying Xiazhen Lin Yamei Shen 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1347-1357,共11页
Camptotheac acuminata Decne is a unique tree species in China with an important secondary metabolite,camptothecin(CPT),used in the treatment of cancer.Nitrogen(N)is an important element that affects plant growth and t... Camptotheac acuminata Decne is a unique tree species in China with an important secondary metabolite,camptothecin(CPT),used in the treatment of cancer.Nitrogen(N)is an important element that affects plant growth and the accumulation of CPT.Reports on the effect of N on CPT synthesis from a genetic perspective are scarce.To explore the effects of different N sources and levels on CPT synthesis in C.acuminata,two-year-old seedlings were fertilized with different concentrations of pure ammonium sulphate,source of ammonium N(NH4+-N),and potassium nitrate for nitrate N(NO3--N).Concentrations of 2.5,5,7.5,and10 g pot-1 NH4+-N and NO3--N were used.The results showed that 7.5 g NH4+-N and NO3--N treatments were best for growth and fresh weight of leaves.Compared with the other treatments,the CPT content,tryptophan synthase and tryptophan decarboxylase activities,and expression of the CaTSB and CaTDCl genes under the 2.5 g NH4+-N and NO3--N treatments peaked significantly at 30 days.However,the expression of CaTDC2 surpassed that of the other two genes at 60 days.Therefore,compared with NH4+-N source,the NO3--N source was more beneficial for growth,and NO3--N was better for CPT yield.Consequently,leaves of C.acuminata treated with 2.5 g NO3--N could be harvested after 30 days to obtain maximum CPT content.CaTDC1 is more closely linked to CPT synthesis.The results of this study improved the production of CPT in C.acuminata via fertilization. 展开更多
关键词 Ammonium sulfate Camptotheca acuminata CAMPTOTHECIN Gene expression Potassium nitrate
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α-Glucosidase inhibitive diarylheptanoids from Ottelia acuminata var.acuminata,a traditional vegetable of Bai Nationality in Yunnan 被引量:1
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作者 Hong-Xing Liu Jun-Zeng Ma +4 位作者 Yan-Song Ye Jian-Jun Zhao Shi-Jie Wan Xin-Yue Hu Gang Xu 《Natural Products and Bioprospecting》 2022年第1期299-309,共11页
Diabetes is an urgent health issue characterized by ethnic and regional variations,and is inseparable from the differ-ent dietary habits.It is worthy to note that the incidence of diabetes in Bai nationality has been ... Diabetes is an urgent health issue characterized by ethnic and regional variations,and is inseparable from the differ-ent dietary habits.It is worthy to note that the incidence of diabetes in Bai nationality has been reported to be much lower than Han in China.As a daily vegetable of Bai,the phytochemical and antidiabetic study of Ottelia acuminata var.acuminata had not been carried out.In this study,41 metabolites with diverse diarylheptanoid(six new ones,Otteacumienes A-F),flavone,sesquiterpenoid,coumarin,lignan,polyacetylene,and alkaloid skeletons were charac-terized from O.acuminata var.acuminata.Among them,the racemic nature of 3 was characterized by chiral resolution and calculated ECD methods.The biological study revealed diarylheptanoids showed significantα-glucosidase inhibi-tory activities with 5 as the most effective one(60-fold stronger than acarbose).Molecular docking studies indicated that these structures have different binding cavities with acarbose.This study demonstrated that O.acuminata var.acuminata might correlated with the low incidence diabetes of Bai and the diarylheptanoids may have potential therapeutic value for diabetes mellitus. 展开更多
关键词 Ottelia acuminata var.acuminata Bai nationality VEGETABLE diARYLHEPTANOIDS Α-GLUCOSIDASE
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Culture techniques and growth characteristics of Dinophysis acuminata and its prey 被引量:1
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作者 佟蒙蒙 周启星 +3 位作者 KULIS M.David 江天久 齐雨藻 ANDERSON M.Donald 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1230-1239,共10页
The dinoflagellate Dinophysis acurninata Claparede & Lachrnann is a toxic alga that causes diarrhetic shellfish poisoning. No Dinophysis species were maintained in culture for a long period of time until 2006 when Pa... The dinoflagellate Dinophysis acurninata Claparede & Lachrnann is a toxic alga that causes diarrhetic shellfish poisoning. No Dinophysis species were maintained in culture for a long period of time until 2006 when Park successfully established D. acuminata in culture using a three-step feeding protocol in which the cryptophyte, Geminigera cryophila, is fed to Myrionecta rubra (=Mesodinium rubrum), a ciliate that is in turn fed to D. acuminata. In this paper, we present the details of culturing D. acuminata from the Northeastern United States. The protocols described herein can be adopted for laboratory studies of this species. The effects of temperature on the growth and ingestion rates of D. acuminata were also examined. The results show that D. acuminata growth rate was 0.23/d at 10℃ and 0.11/d at 4℃when fed M. rubra prey. The maximum prey ingestion rate was 2.80 Dinophysis cell/d at 10℃, although the rate decreased slightly at 4℃. In overall, temperature showed a greater influence on growth rate of D. acuminata than on the ingestion rate under the study conditions, and the quantity of available food was also an important regulator to D. acurninata growth. 展开更多
关键词 dinophysis acuminata Myrionecta rubra Geminigera cryophila growth rate ingestion rate
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DIFFERENTIATION OF PSEUDOCONDYLOMA OF VULVA AND CONDYLOMA ACUMINATA BY DOT BLOT HYBRIDIZATION AND POLYMERASE CHAIN REACTION 被引量:1
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作者 刘跃华 王家璧 司静懿 《Chinese Medical Sciences Journal》 CAS CSCD 1996年第1期53-55,共3页
This study differentiated pseudocondyloma of vulva from condyloma acuminata using dot blot hybridization and polymerase chain reaction (PCR). A total of 27 cases of pseudocondyloma of vulva and 65 cases of condyloma a... This study differentiated pseudocondyloma of vulva from condyloma acuminata using dot blot hybridization and polymerase chain reaction (PCR). A total of 27 cases of pseudocondyloma of vulva and 65 cases of condyloma acuminata were selected for the study. The genital lesions were examined clinically and were biopsied. Each biopsy was subjected to histological examination and HPV DNA analysis by dot blot hybridization and PCR. Dot blot analysis detected HPV DNA in 19(82. 6%) out of 23 cases of condyloma acuminata and 2(25% ) out of 8 cases pseudocondyloma of vulvae (P<0. 05). PCR detected HPV DNA in 51 (92. 7%) out of 55 cases of condyloma acuminata , compared with none in 23 cases of pseudocondyloma (P<0.001 ). HPV DNA was present in the majority of condyloma acuminata specimens. HPV 6 and 11 were the predominant types. Peudocondyloma is probably not associated with HPV. PCR was the most sensitive and useful technique for HPV DNA detection. 展开更多
关键词 pseudocondyloma condyloma acuminata polymerase chain reaction
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Effects of medium nutrition on cell growth and isocamptothecin A and B production by suspension cell culture of Camptotheca acuminata 被引量:1
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作者 张冬艳 Yu Fang Bai Fengwu An Lijia 《High Technology Letters》 EI CAS 2006年第4期446-448,共3页
The effects of initial sucrose concentration, nitrate to ammonium ratio, total N concentration and phosphate concentration in medium on cell growth and isocamptothecin A and B synthesis by suspension call culture of C... The effects of initial sucrose concentration, nitrate to ammonium ratio, total N concentration and phosphate concentration in medium on cell growth and isocamptothecin A and B synthesis by suspension call culture of Camptotheca acuminata were investigated in 250 mL shake flasks. 30 g L^-1 sucrose concentration was beneficial to secondary metabolites synthesis. The cell growth and metabolites synthesis were also affected by the ratio of NO3^-/NH4^+ , and nitrate was tavourable for cell growth. The maximum dry weight was achieved when nitrate was used as the sole N souree. The effect of total initial N on the cell cultures was also investigated with NO3^-/NH4^+ ratio of 1 : 2. The final dry cell weight was similar throughout culture period and 50 mM initial N was favourable for secondary metabolite synthesis. 50 mM initial phosphate concentration facilitated both cell growth and secondary metabolites synthesis. 展开更多
关键词 Camptotheca acuminata isocamptothecin A and B plant cell culture
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罕见抗-Di^(b)合并抗-E抗体的实验室检测与临床输血
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作者 吕红娟 朱海峰 《临床血液学杂志》 2025年第10期792-795,共4页
目的对1例十二指肠腺癌患者鉴定出罕见高频抗体(抗-Di^(b)),实施献血者Di^(b)抗原筛选和自体输血,保证临床输血安全,探讨稀有血型血液保障方案。方法运用血型血清学试验,使用试剂红细胞和稀有血型献血者红细胞检测患者血清,使用试剂抗... 目的对1例十二指肠腺癌患者鉴定出罕见高频抗体(抗-Di^(b)),实施献血者Di^(b)抗原筛选和自体输血,保证临床输血安全,探讨稀有血型血液保障方案。方法运用血型血清学试验,使用试剂红细胞和稀有血型献血者红细胞检测患者血清,使用试剂抗血清检测患者红细胞和献血者红细胞血型抗原;在Microlab STAR全自动样品处理系统编程,以稀有血型单克隆抗-Di^(b)抗体对献血者实施抗原筛选;对患者实施术前自体采血。结果患者为A型,RhD阳性,其稀有血型为Di^(b)阴性,抗-Di^(b)合并抗-E同种抗体引起配血困难;使用抗-Di^(b)单克隆抗体筛选献血者,从1090例献血者中发现1例供者,血量2个单位;术前采集自体血400 mL;术中输入400 mL自体血和2个单位稀有异体血,手术顺利。结论鉴定发现2例Di^(b)阴性稀有血型;采取对献血者实施抗原筛选寻找相合血液联合自体输血策略成功解决患者手术用血问题;建立起了1种自动化抗原筛选模式用于稀有血型库工作。 展开更多
关键词 稀有血型 抗原筛选 自体输血 抗-di^(b) 抗-E
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Agrobacterium-mediated genetic transformation of Camptotheca acuminata
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作者 王慧梅 祖元刚 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期316-318,共3页
UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acum... UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acuminata on the basis of evaluations of several factors affecting Agrobacterium-mediated DNA transfer rate. The highest transformation rate was achieved when pre-cultttred leaf explants were infected with an Agrobacterium culture corresponding to OD600 (0.5) for 10 min, and cultured on explant regeneration medium for three days. The results of Southern hybridization showed that genomic DNA of the kanamycin-resistant shoots to an UGPase gene probe substantiated the integration of the transgene. Transformation efficiency (6%) was achieved under the optimized transformation procedure, This system should facilitate the introduction of important useful genes into C, acuminata. 展开更多
关键词 Genetic transformation Camptotheca acuminata UGpase gene
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Effects of 5-Azacytidine(AZA)on the Growth,Antioxidant Activities and Germination of Pellicle Cysts of Scrippsiella acuminata(Dinophyceae)
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作者 WANG Zhaohui ZHANG Jianneng +2 位作者 TANG Tao ZHANG Yuning HU Ren 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1660-1668,共9页
In this study,we investigated the effects of different concentrations of 5-azacytidine(AZA),a DNA methyltransferase in-hibitor,on the growth,antioxidant activities and germination of pellicle cysts of Scrippsiella acu... In this study,we investigated the effects of different concentrations of 5-azacytidine(AZA),a DNA methyltransferase in-hibitor,on the growth,antioxidant activities and germination of pellicle cysts of Scrippsiella acuminata.The purpose of this study is to understand the toxic effects of AZA on marine microalgae,and to demonstrate the effect of DNA methyltransferase inhibitors on the germination of pellicle cysts.Results showed that AZA inhibited the growth of S.acuminata significantly,and displaced a clear dose-dependent inhibition trend with the 96h EC50 of 146.77μmolL^(-1)(35.84mgL^(-1)).Pellicle cysts of S.acuminata were less sensitive to AZA than the vegetative cells,and the EC50 value of AZA to the germination of pellicle cysts of S.acuminata was 8.08mmolL^(-1)(1.97g L^(-1)).After exposed to AZA,the antioxidant activities in S.acuminata responded rapidly and significantly.Among them,soluble pro-tein and superoxide dismutase(SOD)were more sensitive to AZA,and significant promotions occurred after exposed to 10μmolL^(-1)AZA for 24h.Meanwhile,malondialdehyde(MDA)contents in algal cells did not change significantly after exposed to low concen-trations of AZA,but increased firstly and then decreased under high concentration of AZA.The glutathione(GSH)levels in S.acu-minata increased significantly under high concentrations of AZA,and remained unchanged at low concentrations of AZA.The results suggested that the enhanced protein level and SOD activity of S.acuminata eliminated reactive oxygen species(ROS)to a certain ex-tent,and thus protected algal cells against damages of ROS caused by AZA. 展开更多
关键词 5-AZACYTIdiNE Scrippsiella acuminata pellicle cysts toxicity superoxide dismutase glutathione MALONdiALDEHYDE
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Improvement of Selected Morphological, Physiological, and Biochemical Parameters of Banana (Musa acuminata L.) Using Potassium Silicate under Drought Stress Condition Grown in vitro
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作者 Hosny Abdel Aziz Mohamed Sharaf +7 位作者 Magdy Omar Ahmed Abou El-Yazied Nada Ibrahim AlJwaizea Shaimaa Ismail Mohamed M.A.Omar Khadiga Alharbi Amr Elkelish Moataz Tawfik 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1019-1036,共18页
Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees.The growth and productivity of Musa spp are severely impacted by the ... Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees.The growth and productivity of Musa spp are severely impacted by the gradual degradation of water resources and the erratic distribution pattern of annual precipitation amount.The aim of the work includes increased drought tolerance in light of water scarcity in the world as a result of the bananas’being gluttonous for water needs.This investigation was carried out from 2019 to 2020 to study the effect of potassium silicate on morphological growth and biochemical parameters of Musa acuminata L under drought stress by PEG.As a result,drought stress reduced the morphological characteristics such as shoots number,shoot length,roots number,and survival percentage and biochemical characteristics such as chlorophyll a,b,carotenoids,stomatal status,and RWC.While proline content increased in the leaf of M.acuminata L.Media complemented with K2SiO3(2 to 6 mM)either individually or in combination with PEG led to an improvement in all morphological and biochemical characteristics.The activities of CAT,POD,and PPO enzymes increased significantly compared to control.Furthermore,the lowest PPO,CAT,and POD activity were achieved.Additionally,K2SiO3 treatments under drought stress successfully enhanced the leaf stomatal behavior.Our results suggest that K2SiO3 can help to maintain plant integrity in the tested cultivar under drought stress. 展开更多
关键词 Musa acuminata L potassium silicate photosynthetic pigments STOMATA enzymatic activity
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pMDI桉木胶合板工艺因子对其力学性能影响的研究 被引量:2
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作者 潘礼成 黄强 +3 位作者 李骜 罗晓西 任一萍 覃琼林 《林产工业》 北大核心 2025年第4期18-26,共9页
通过正交试验研究pMDI胶黏剂施胶量、单板含水率、热压温度及时间等关键工艺因子对桉木胶合板物理力学性能的影响,并优化热压工艺,最终得到符合高效连续平压胶合板生产线需求的工艺参数。结果表明:当热压压力为0.9 MPa时,胶合板的最佳... 通过正交试验研究pMDI胶黏剂施胶量、单板含水率、热压温度及时间等关键工艺因子对桉木胶合板物理力学性能的影响,并优化热压工艺,最终得到符合高效连续平压胶合板生产线需求的工艺参数。结果表明:当热压压力为0.9 MPa时,胶合板的最佳工艺方案为施胶量50 g/m^(2),热压温度190℃,热压时间40 s/mm,单板含水率16%。为提高生产效率并降低成本,进一步优化工艺,提出并验证了符合连续平压胶合板生产线的优化方案。优化后的生产工艺方案为施胶量40 g/m^(2),热压温度190℃,热压时间25 s/mm,单板含水率16%。采用该工艺生产的胶合板产品的Ⅰ类胶合强度可达1.43 MPa。研究结果可为pMDI胶合板自动化生产提供理论基础和数据支撑。 展开更多
关键词 桉木 胶合板 聚合4 4’-二苯基甲烷二异氰酸酯(pMdi) 工艺因子 力学性能
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青枯菌GMI 1000菌株c-di-GMP代谢酶调控基因vsrD功能研究
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作者 杨晓欣 许景升 +3 位作者 徐进 韩文超 李志明 冯洁 《植物保护》 北大核心 2025年第3期102-112,共11页
青枯菌Ralstonia solanacearum是全球作物生产中的一种重要病原细菌。由青枯菌引起的植物细菌性枯萎病(简称青枯病)危害数百种经济作物并造成严重经济损失。环二鸟苷酸(cyclic diguanylate,c-di-GMP)是一种广泛存在于细菌中的第二信使分... 青枯菌Ralstonia solanacearum是全球作物生产中的一种重要病原细菌。由青枯菌引起的植物细菌性枯萎病(简称青枯病)危害数百种经济作物并造成严重经济损失。环二鸟苷酸(cyclic diguanylate,c-di-GMP)是一种广泛存在于细菌中的第二信使分子,通过调控生物膜形成、运动性等影响病原菌致病力。但在青枯菌中,c-di-GMP的调控网络并不清楚。本试验以青枯菌GMI 1000中的c-di-GMP降解酶基因gedrG缺失突变体菌株(ΔgedrG-GMI)为研究对象,将pMiniHimarI RB1质粒通过双亲共结合法导入ΔgedrG-GMI突变体,筛选运动性表型恢复的转座子插入突变体(transposon mutagenesis),共鉴定了13272株转座子插入突变体。其中,转座子插入vsrD基因时,ΔgedrG-GMI运动性恢复为野生型水平。分析表明vsrD基因缺失后,突变株运动性极显著增强,胞内c-di-GMP水平降低,致病力丧失,vsrD基因互补菌株运动性恢复至缺失前水平。以上结果表明,vsrD参与了青枯菌GMI 1000中c-di-GMP调控通路,影响GMI 1000运动性,且与致病性密切相关。 展开更多
关键词 青枯菌 C-di-GMP 致病力 运动性 调控
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巧用DIS无系统误差验证牛顿第二定律 被引量:1
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作者 赵登峰 《中学理科园地》 2025年第1期77-80,共4页
通过巧妙设计实验装置并且用DIS实验辅助实验过程中物理量的测量消除了实验中系统误差,有力地验证了牛顿第二定律。
关键词 实验 diS 系统误差 牛顿第二定律
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用DISLab和Tracker软件研究“绳碰钉”问题
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作者 王思尧 张敏 +1 位作者 方伟 黄声达 《物理通报》 2025年第10期131-134,共4页
“绳碰钉”问题是圆周运动中一个比较典型的瞬时变化问题,因其复杂性和抽象性,对高中生来说较难理解.实验利用简单改制后的DIS机械能守恒实验器和视频分析软件Tracker研究“绳碰钉”问题中的变量和不变量,帮助学生更清晰直观地理解这类... “绳碰钉”问题是圆周运动中一个比较典型的瞬时变化问题,因其复杂性和抽象性,对高中生来说较难理解.实验利用简单改制后的DIS机械能守恒实验器和视频分析软件Tracker研究“绳碰钉”问题中的变量和不变量,帮助学生更清晰直观地理解这类问题.同时基于实验进行题目创新,打破传统出题思路,深入考查学生对这类问题的理解. 展开更多
关键词 diS 圆周运动 绳碰钉 Tracker软件
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c-di-AMP为佐剂的重组卡介苗免疫对小鼠白色脂肪的调节作用
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作者 董梦娟 常宇骁 +8 位作者 宁唤唤 路延之 康健 徐铭泽 代婷 李嘉玲 郝乐冉 张琳娜 柏银兰 《中国人兽共患病学报》 北大核心 2025年第4期370-375,共6页
目的研究c-di-AMP为佐剂的重组卡介苗(rBCG)调节小鼠附睾白色脂肪(eWAT)代谢及免疫的作用和机制。方法SPF级雄性C57BL/6小鼠经静脉免疫卡介苗(BCG)和重组卡介苗(rBCG),监测小鼠体重变化。分离并称重小鼠eWAT重量,血球仪计血管基质成分(S... 目的研究c-di-AMP为佐剂的重组卡介苗(rBCG)调节小鼠附睾白色脂肪(eWAT)代谢及免疫的作用和机制。方法SPF级雄性C57BL/6小鼠经静脉免疫卡介苗(BCG)和重组卡介苗(rBCG),监测小鼠体重变化。分离并称重小鼠eWAT重量,血球仪计血管基质成分(SVFs)数量。制备小鼠脂肪组织切片,HE染色后显微镜下观察和比较各组小鼠eWAT脂肪细胞大小、数量和形态以及冠状结构(CLS)形成等变化。qRT-PCR检测各组小鼠脂肪代谢相关因子、细胞因子和衰老相关基因的转录水平。结果BCG和rBCG免疫小鼠体重随时间逐渐增加,rBCG免疫诱导eWAT比重增加,SVFs数量降低。HE染色结果显示,BCG免疫促进eWAT脂肪细胞增生和rBCG免疫促进脂肪细胞肥大,BCG和rBCG免疫均可诱导eWAT中CLS形成。qRT-PCR检测结果显示,rBCG免疫可抑制eWAT脂肪分解和能量消耗相关基因表达。BCG免疫对细胞因子转录作用影响不大,而rBCG可诱导IFN-γ和IL-1Ra显著表达,抑制IL-15和IL-2的转录,但不诱导衰老相关基因的表达。结论rBCG免疫可诱导eWAT脂肪细胞肥大,其机制与抑制eWAT脂肪分解及调节细胞因子表达有关。 展开更多
关键词 卡介苗 重组卡介苗 环二腺苷酸 白色脂肪 脂肪代谢 细胞因子
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变力作用下的动量定理DIS实验教学改进
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作者 许菖 林方婷 刘爱云 《物理通报》 2025年第3期114-117,共4页
在传统DIS实验中,研究变力作用下的动量定理基本上以专用软件为主,实验步骤过于简单,容易限制学生的思维.利用通用软件,引导学生自主设计实验方案和数据表格,对实验误差进行分析,提出改进方案加以验证.改进后的实验教学方式对于发展学... 在传统DIS实验中,研究变力作用下的动量定理基本上以专用软件为主,实验步骤过于简单,容易限制学生的思维.利用通用软件,引导学生自主设计实验方案和数据表格,对实验误差进行分析,提出改进方案加以验证.改进后的实验教学方式对于发展学生的物理核心素养具有显著优势. 展开更多
关键词 diS实验 通用软件 变力 动量定理 误差分析
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基于物理学科核心素养的高中物理DIS实验教学实践探究 被引量:1
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作者 蓝树明 《国家通用语言文字教学与研究》 2025年第3期49-51,共3页
高中物理作为科学教育的重要组成部分,其实验教学在培养学生物理核心素养方面有着独特的作用。传统实验教学在一定程度上受到仪器精度、数据采集与处理效率等因素的限制。而DIS实验教学通过数字化信息系统,实现了实验数据的实时采集、... 高中物理作为科学教育的重要组成部分,其实验教学在培养学生物理核心素养方面有着独特的作用。传统实验教学在一定程度上受到仪器精度、数据采集与处理效率等因素的限制。而DIS实验教学通过数字化信息系统,实现了实验数据的实时采集、处理和分析,能够更加准确地呈现物理现象和规律,有效提高了实验的精确度和效率,为高中物理实验教学带来了新的思路。对此,本文通过分析DIS实验的特点,研究基于物理学科核心素养的高中物理DIS实验教学的优势,在此基础上探讨基于物理学科核心素养的高中物理DIS实验教学实践策略。 展开更多
关键词 学科核心素养 高中物理 diS实验教学
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