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基于问题驱动的“DNA是主要的遗传物质”教学设计

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生物学通报 2024年第6期59卷 32-35页

作者：钱珂楠虞驰宁波市四明中学浙江宁波315043 宁波市第四中学浙江宁波315016

以“DNA是主要的遗传物质”一节教学为例,阐述基于问题驱动的课堂教学设计。以问题驱动贯穿整节课的教学,利用教材中的插图,帮助学生理解“DNA是主要的遗传物质”探索过程中的几个重要实验,提升学生科学思维和科学探究能力,提高课堂效率。

关键词：问题驱动遗传物质教学设计

Fuzzy 控制的发电厂冷却水管网自动补水系统

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沈阳工业学院学报 1998年第1期17卷 12-16页

作者：王大志王克难于洋李福全沈阳工业学院自动控制系锦州畜牧兽医学校沈阳工业学院

通过对某发电厂冷却水管网补水系统工艺的分析，阐述了在该系统应用Ｆｕｚｚｙ控制的必要性，并用８０９８单片机构成了Ｆｕｚｙ控制器．实际运行情况表明，系统性能良好，可靠性高．

关键词：补水系统微机控制模糊控制冷却水管网发电厂

A Universal Atomic Substitution Conversion Strategy Towards Synthesis of Large‑Size Ultrathin Nonlayered Two‑Dimensional Materials

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Nano-Micro Letters 2021年第11期13卷 79-91页

作者： Mei Zhao Sijie yang kenan Zhang Lijie Zhang Ping Chen Sanjun yang yang Zhao Xiang Ding Xiaotao Zu Yuan Li Yinghe Zhao Liang Qiao Tianyou Zhai School of Physics University of Electronic Science and Technology of China(UESTC)Chengdu 610054People’s Republic of China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074People’s Republic of China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province Institute of New Materials and Industrial TechnologiesCollege of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035People’s Republic of China

Nonlayered two-dimensional(2D)materials have attracted increasing attention,due to novel physical properties,unique surface structure,and high compatibility with microfabrication ***,owing to the inherent strong covalent bonds,the direct synthesis of 2D planar structure from nonlayered materials,especially for the realization of large-size ultrathin 2D nonlayered materials,is still a huge ***,a general atomic substitution conversion strategy is proposed to synthesize large-size,ultrathin nonlayered 2D *** nonlayered CdS as a typical example,large-size ultrathin nonlayered CdS single-crystalline flakes are successfully achieved via a facile low-temperature chemical sulfurization method,where pre-grown layered CdI2 flakes are employed as the precursor via a simple hot plate assisted vertical vapor deposition *** size and thickness of CdS flakes can be controlled by the CdI2 *** growth mechanism is ascribed to the chemical substitution reaction from I to S atoms between CdI2 and CdS,which has been evidenced by experiments and theoretical *** atomic substitution conversion strategy demonstrates that the existing 2D layered materials can serve as the precursor for difficult-to-synthesize nonlayered 2D materials,providing a bridge between layered and nonlayered materials,meanwhile realizing the fabrication of large-size ultrathin nonlayered 2D materials.

关键词： Nonlayered 2D materials Large-size ultrathin CdS flakes Atomic substitution conversion Layered-nonlayered structural transformation

不同舱门开启条件下空客A330客舱人员疏散特性

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沈阳航空航天大学学报 2024年第4期41卷 67-75页

作者：刘天奇刘克楠沈阳航空航天大学安全工程学院沈阳110136

为探讨不同舱门开启条件下空客A330客舱人员疏散特性,使用Pathfinder软件数值模拟,探究全部舱门开启、应急舱门无法开启、前客舱门无法开启、后客舱门无法开启4种情形下的人员疏散特性。研究发现:全部舱门开启条件下人员疏散用时63.3 s... 详细信息

为探讨不同舱门开启条件下空客A330客舱人员疏散特性,使用Pathfinder软件数值模拟,探究全部舱门开启、应急舱门无法开启、前客舱门无法开启、后客舱门无法开启4种情形下的人员疏散特性。研究发现:全部舱门开启条件下人员疏散用时63.3 s,应急舱门无法开启时人员疏散用时118.3 s,3、4、7、8号舱门的人流量每秒分别下降0.09、0.2、0.09、0.04人,公务舱门和后客舱门出现堵塞。前客舱门无法打开时,人员疏散用时64 s,从3、4、5、6号舱门撤离人数分别为47、48、52、50人,表明前客舱门无法开启未对疏散时间造成显著影响。后客舱门无法开启时,人员疏散用时112.3 s,从3、4、5、6号舱门第一个人撤离到最后一个人撤离的时间间隔分别为67.7、67.6、109.9、107.1 s。这表明经济舱乘客更倾向于从5、6号舱门逃生,从而延长了疏散时间。研究结果对掌握不同舱门开启条件下人员疏散特性提供了参考。

关键词：客舱人员疏散特性应急舱门 Pathfinder软件疏散时长

聚乙烯醇纤维掺量对混凝土动态力学性能的影响

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青海大学学报 2024年第3期42卷 64-70页

作者：张炳锋高士武杨晓林刘柯楠青海大学土木水利学院青海西宁810016 青海省建筑节能材料与工程安全重点实验室青海西宁810016 青海省压缩空气储能重点实验室青海西宁810016

为探究冲击荷载下不同体积掺量的聚乙烯醇纤维对混凝土动态压缩性能的影响,采用∅75 mm分离式Hopkinson压杆进行了基于不同体积参数的PVARC试件冲击压缩试验。结果表明:随着纤维掺量的提高,PVARC试件的破坏程度逐步减小,应变率在185 s^(... 详细信息

为探究冲击荷载下不同体积掺量的聚乙烯醇纤维对混凝土动态压缩性能的影响,采用∅75 mm分离式Hopkinson压杆进行了基于不同体积参数的PVARC试件冲击压缩试验。结果表明:随着纤维掺量的提高,PVARC试件的破坏程度逐步减小,应变率在185 s^(-1)附近时,0.75%的试件动态峰值应力比普通混凝土提高了50%。该研究结果可为在实际工程中选择合适的纤维掺量提供参考。

关键词： Hopkinson压杆 PVA纤维纤维混凝土冲击荷载

Co/MOF-808(Zr)复合材料的制备及其对有机磷化合物的降解性能

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天津工业大学学报 2024年第1期43卷 50-55页

作者：黄艳凤焦克楠王晓荣潘杰万冬天津工业大学化学工程与技术学院天津300387

为了解决普通单金属MOFs材料几乎不能直接将双(4-硝基苯)磷酸酯(BNPP)直接降解为毒性更低的对氨基苯酚(4-AP)的问题,通过油浴法制备出MOF-808(Zr)后,采用后修饰法将草酸钴负载于MOF-808(Zr)上,制备出Co/MOF-808(Zr)复合材料,并对所制材... 详细信息

为了解决普通单金属MOFs材料几乎不能直接将双(4-硝基苯)磷酸酯(BNPP)直接降解为毒性更低的对氨基苯酚(4-AP)的问题,通过油浴法制备出MOF-808(Zr)后,采用后修饰法将草酸钴负载于MOF-808(Zr)上,制备出Co/MOF-808(Zr)复合材料,并对所制材料进行XRD和TEM表征。结果表明:MOF-808(Zr)具有高晶体结构稳定性,Co/MOF-808(Zr)的粒径在250 nm左右且分布均匀;Co/MOF-808(Zr)通过级联反应成功将有机磷神经毒剂模拟物BNPP直接降解为毒性更低的4-AP,而非一般的毒性较高的降解产物对硝基苯酚(4-NP)。其最佳级联降解反应条件为:温度45℃,Co/MOF-808(Zr)剂量为2 mg/mL,底物BNPP为0.6 mmol/L,硼氢化钠0.06 mmol/L。实践得出,Co/MOF-808(Zr)在将有机磷化合物直接降解为毒性更低的4-AP方面表现出良好的应用潜力。

关键词： Co/MOF-808(Zr) 级联反应水解BNPP 氢化4-NP 有机磷化合物降解

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耦合主成分分析下煤矿矿井突水水源识别方法

能源与环保 2024年第4期46卷 38-43页

作者：邢楷单耀王克南樊林林邹阳晋煤集团技术研究院有限责任公司山西晋城048006 华北科技学院河北廊坊065201

煤矿矿井突水会导致矿井内部水位迅速上升,对煤矿生产造成严重影响,甚至导致煤矿停产。开展矿井突水水源识别可以及早发现突水风险,从而保障煤矿生产和矿工的生命安全。为此,提出一种耦合主成分分析下煤矿矿井突水水源识别方法。根据水... 详细信息

煤矿矿井突水会导致矿井内部水位迅速上升,对煤矿生产造成严重影响,甚至导致煤矿停产。开展矿井突水水源识别可以及早发现突水风险,从而保障煤矿生产和矿工的生命安全。为此,提出一种耦合主成分分析下煤矿矿井突水水源识别方法。根据水源化学各组分间差异性确定突水水源判别指标变量,从煤矿矿井含水层随机选取18个水样化学信息,通过耦合主成分分析获得各水源组间相关性,提取4个重要的主成分表征所有样本信息特征,结合协方差矩阵、Fisher判别得到各类型水源组别的中心距离,识别出突水水源类型。实验结果表明,所提方法能够解决样本信息各变量间信息叠加问题,提升了突水水源识别准确率。

关键词：耦合主成分分析突水水源化学组分 Fisher判别中心值距离

Profiling interfacial reaction features between diamond and Cu-Sn-Ti active filler metal brazed at 1223 K

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Journal of Materials Science & Technology 2022年第36期131卷 100-105页

作者： Yonggang Fan kenan Li Haodong Li Cong Wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) School of MetallurgyNortheastern UniversityShenyang 110819China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasives&Grinding Co.Ltd.Zhengzhou 450001China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Diamond/Cu-Sn-Ti composites have been successfully prepared by cold-press forming in conjunction with high-temperature vacuum active brazing at 1223 *** wetting behaviors between diamond and filler metal,interfacial characteristics of the reaction layer,and wear resistance of the bulky composite have been fully *** is revealed that all diamond particles can only be fully coated when the TiH_(2)content exceeds 5 wt%,below which sharp edges on diamond can still be *** interfacial reaction layer is found to be composed of TiC,the thickness of which is demonstrated to increase as a function of TiH_(2)content,arriving at the peak value of 1.70μm and remaining almost constant *** is further shown that the maximum wear resistance occurs approaching 5 wt%TiH_(2)*** mechanisms responsible for such interesting phenomena have been postulated.

关键词： Diamond Cu-Sn-Ti Brazing Interfacial layer Powder metallurgy

The assessment of structural changes on optic nerve head and macula in primary open angle glaucoma and ocular hypertension

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International Journal of Ophthalmology(English edition) 2018年第10期11卷 1631-1637页

作者： kenan Dagdelen Emrah Dirican Department of Ophthalmology Eskisehir Yunus Emre State Hospital Department of Ophthalmology Konya Training and Research Hospital

AIM：To assess morphological changes in macula, retinal nerve fiber layer （RNFL） and optic nevre head （ONH） of cases with primary open angle glaucoma （POAG） and ocular hypertension （OH） with spectral domain optic coherence tomography （OCT）.METHODS：This study included 109 eyes from 62 POAG patients, 50 eyes from 30 OH patients, and 101 eyes from 53 healthy volunteers. Data gained by OCT were compared with perimetry indexes. ONH, RNFL and macula analysis were performed for all subjects. Rim area, disc area,average cup/disc （C/D） ratio, vertical C/D ratio, cup volume data were recorded during ONH analysis. Average RNFL thickness and the thickness of four quadrants （superior,inferior, nasal and temporal） was established in *** total, nine macular quadrants involving the foveal region mentioned in the Early Treatment Diabetic Treatment Study（ETDRS） template were measured, and average macular thickness and macular volume data were recorded during macula analysis. Differences between groups were evaluated with the one-way ANOVA test. Tukey’s multiple comparison test was performed to detect difference between ***-operating characteristic （ROC） analysis was done for early stage POAG patients to establish sensitivity and specificity of chosen parameters in early stage *** under the receiver operating characteristic （AUROC）values were calculated to compare ROC ***：Statistically significant differences were found in all ONH parameters, except optic disc area. Neuroretinal rim area was identified as the parameter with the highest difference between groups （F=21.72, P〈0.05）. The highest correlation between ONH parameters and perimetry was observed at neuroretinal rim region （r=0.487）. Inferior RNFL thickness was established as the parameter with the highest difference between groups among RNFL parameters. In the mean of all glaucoma patients, the highest correlation between data handled with OCT and mean deviation was observed in RNFL thickness.

关键词： glaucoma ocular hypertension optic coherence tomography