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智能科学与技术学报, 2021 进化集成学习结合了集成学习和进化算法两方面的优势，并在机器学习、数据挖掘和模式识别等领域被广泛应用。首先对进化集成学习算法的理论基础、组成结构及分类情况进行了概述。然后根据进化算法在集成学习中的优化任务，从样本选择、特征选择、集成模型参数组合优化、集成模型结构优化以及集成模型融合策略优化几个方面对当前进化集成学习领域的一些代表性研究成果进行了详细的综述，并分析和总结了各种进化集成学习算法的特点。最后对现有的进化集成研究的优缺点进行探讨，并给出了未来的研究方向。
胡毅 +4 more
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Study on the kinetics of dimethyl ether one-step synthesis from syngas(合成气一步法制二甲醚的动力学研究)
Zhejiang Daxue xuebao. Lixue ban, 2003 采用固定床积分反应器,研究了用浸渍法制备的CuO-ZnO/Y-zeolite双功能催化剂上CO加氢直接合成二甲醚的反应动力学.按一氧化碳加氢先合成甲醇,再由甲醇脱水生成二甲醚两步串联的反应机理,分别建立了动力学模型,并对该催化剂上甲醇合成及甲醇脱水的机理作了探讨.模型的计算值和实验值能较好吻合,两步反应的表观治化能分别为27.98 kJ/mol和30.62kJ ...
JIANGDa-hao(江大好) +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2011 报道了一种酶促-化学法合成光学纯吗啉酮凝血酶抑制剂的新途径.以马来酸酐和氨基醇为起始原料，一锅法合成N-苄基吗啉-3-酮-2-乙酸甲酯；再用脂肪酶CAL-B在甲基叔丁基醚/水（体积分数=1/9）混合溶剂中将其选择性水解，制备光学纯(R)-N-苄基吗啉-3-酮-2-乙酸；经过酰胺化、还原/胺解，得到(R)-N-苄基吗啉-3-酮-2-乙酰（4-脒基）苄胺；所得化合物结构经IR，1H NMR，13C NMR表征确证.文中还讨论了酶源、溶剂、含水量、反应时间等因素对水解拆分的影响.
YEHai-peng(叶海朋) +4 more
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蔗糖脂肪酸酯的制备及应用研究进展Progress in preparation and application of sucrose fatty acid ester
Zhongguo youzhi, 2022 蔗糖脂肪酸酯简称蔗糖酯，是一种良好的表面活性剂，被普遍应用于食品工业。蔗糖酯的合成方法主要包括化学法和酶法，对蔗糖酯的化学合成法进行了详细介绍，概述了酰氯酯化法及酯交换法的操作步骤、优选工艺及优缺点，并与酶法进行了对比。概述了蔗糖酯的结构、理化性质、应用及工业发展现状，以期为蔗糖酯的工业化生产提供参考。 Sucrose fatty acid ester, sucrose ester for short, is a good surfactant and is widely used in food ...
刘伟康，蓝平，陈龙 LIU Weikang, LAN Ping, CHEN Long
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Zhejiang Daxue xuebao. Lixue ban, 2004 釆用半经验AMI量子化学方法计算了两类非甾类终止妊娠化合物的物理化学参数，并用多元线性回归分析法对所研究化合物的代谢强度进行QSAR研究，得到了较好的结果.两个模型互相验证，结果一致，有较高的预测能力.根据所建立的模型，化合物较高的生成热以及主要代谢位置上的前沿电子密度均为代谢的不利因素，这可能与化合物体内代谢历程有关.
HUGui-xiang(胡桂香) +5 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Decomposition is the transformation of dead organic matter into its inorganic constituents. In most biomes, decomposition rates can be accurately predicted with simple mathematical models, but these models have long under‐predicted decomposition in globally extensive ...
Heather L. Throop +8 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Grasslands worldwide are experiencing severe degradation due to overgrazing, climate change and anthropogenic disturbances, resulting in substantial declines in biodiversity and ecosystem functioning.
Xiaoqi Wang +5 more
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Zhejiang Daxue xuebao. Lixue ban, 2002 由1,5-二氮环辛烷和手性酰胺醇3反应生成带手性侧臂的1,5-二氮环辛烷化合物2,后者与间二苄溴缩合得到新的桥连化合物1,其结构经元素分析、质谱、红外和1H、13 C核磁等得到了证实.在合成的基础上,用分子力学MM2方法分析了化合物2和1的空间优势构象,取得了它们的最低能量值,和已知类似化合物的晶体结构相比较,确认了化合物优势构象的合理性,且易和金属离子形成稳定配合物.
MEIJiang-hua(梅江华) +3 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract The stoichiometric ratios of carbon (C), nitrogen (N) and phosphorus (P) serve as important indicators for assessing nutrient balance in forest ecosystems, but their relationships with photosynthetic dynamics require deeper characterization.
Minghao Chen +9 more
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The collective application of shorebird tracking data to conservation
Conservation Biology, EarlyView.Abstract Addressing urgent conservation issues, such as the drastic declines of North American migratory birds, requires creative, evidence‐based, efficient, and collaborative approaches. The abundance of over 50% of monitored North American shorebird populations has declined by over 50% since 1980. To address these declines, we developed a partnership
Autumn‐Lynn Harrison +71 more
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