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Journal of Genetics and Genomics 2009年第3期36卷 173-183页

作者： Junzhou li yan Xie Anyong dai lifeng liu Zichao li Key Laboratory of Crop Genomics and Genetic Improvement of Ministry of Agriculture and Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100193 China

Phosphorous （P） deficiency is a major restraint factor for crop production and plants have developed several mechanisms to adapt to low P stress. In this study, a set of 271 introgression lines （ILs） were used to characterize the responses of seedlings to low P availability and to identify QTLs for root traits, biomass, and plant height under P-deficiency and P-sufficiency conditions. Plant height, total dry weight, shoot dry weight, and root number were inhibited under P-deficiency, whereas maximum root length （MRL） and root-shoot ratio （RS） were induced by P-deficiency stress. Relative MRL （RMRL, the ratio of MRL under P-deficiency to MRL under P-sufficiency con- dition） and relative RS （RRS） were used to evaluate P-deficiency tolerance at the seedling stage. A total of 24 additive QTLs and 29 pairs of epistatic QTLs were detected, but only qRN4 was detected in both conditions. This suggested that different mechanisms may exist in both P supply levels. QTLs for adaptive traits （RMRL, RRS, RRV, and RRDW） and qRN4 consistently expressed to increase trait stability may contribute to P-deficiency tolerance. Twelve intervals were cluster regions of QTLs for P-deficiency tolerance, and one QTL （qRRSS） showed pleiotropic effects on P-deficiency tolerance and drought tolerance. These interesting QTLs can be used in marker-assisted breeding through the target ILs.

关键词： introgression lines phosphorous deficiency tolerance QTL mapping rice root traits

Accelerated effect on Mitsunobu reaction via bis-N-tert-butoxycarbonylation protection of 2-amino-6-chloropurine and its application in a novel synthesis of penciclovir

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第10期14卷 760-766页

作者： li-yan dai Qiu-long SHI Jing ZHANG Xiao-zhong WANG Ying-qi CHEN Department of Chemical and Biological Engineering Zhejiang University

Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via *** bis-Boc protected 2-amino-6-chloropurine also shows excellent activity and N9 selectivity in the coupling with various alcohols by a Mitsunobu ***,a new practical and efficient method is established for the synthesis of penciclovir(PCV) from bis-Boc-2-amino-6-chloropurine 9 and the side chain of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxane 5—the latter being a more easily prepared cyclic precursor of the diacetate side chain used in the conventional *** coupling of 9 with 5 proceeded regioselectively at a N9 position of purine derivative for a good yield under Mitsunobu conditions.

关键词： 2-amino-6-chloropurine Mitsunobu reaction bis-Boc protection Penciclovir(PCV)

Dicyclopentyl azodicarboxylate(DCpAD):A new alternative azo-reagent for the Mitsunobu reaction

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Chinese Chemical Letters 2011年第9期22卷 1047-1050页

作者： Jian Hai yang li yan dai Xiao Zhong Wang Ying Qi Chen Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China

Dicyclopentyl azodicarboxylate is introduced as a new azo-reagent which can be conveniently prepared in two steps and be used in the Mitsunobu reaction. Though there are no distinct difference of reactivity between DC... 详细信息

关键词： Dicyclopentyl azodicarboxylatc Mitsunobu reaction Azo-reagent

高效的磁性NiCo2O4纳米粒子催化脑文格尔缩合反应的研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第1期21卷 74-84页

作者： yang-yang FANG Xiao-zhong WANG Ying-qi CHEN li-yan dai Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological Engineering Zhejiang University

目的:脑文格尔缩合反应已被广泛应用于精细化学品、药物、香料和化妆品等领域,是重要的有机合成反应之一。传统的缩合反应存在催化剂稳定性差、分离难、催化活性低等问题。本文旨在探讨NiCo2O4的制备方法与结构的关系和催化剂用于脑文... 详细信息

目的:脑文格尔缩合反应已被广泛应用于精细化学品、药物、香料和化妆品等领域,是重要的有机合成反应之一。传统的缩合反应存在催化剂稳定性差、分离难、催化活性低等问题。本文旨在探讨NiCo2O4的制备方法与结构的关系和催化剂用于脑文格尔缩合反应的条件对性能的影响。创新点:1.通过采用不同的煅烧温度,确定合成NiCo2O4尖晶石催化剂的最适温度,以减少NiO的生成;2.优化反应条件,使苯甲醛和丙二腈的缩合反应收率达到99%;3.获得的NiCo2O4催化剂的稳定性很高,在循环20次后催化性能仍保持不变。方法:1.通过X射线单晶衍射和傅里叶红外光谱分析,推断在不同煅烧温度下合成的催化剂的组成,并确定最佳煅烧温度(图2和3);2.对NiCo2O4尖晶石催化剂进行透射电镜、二氧化碳/氨气程序升温脱附和氮气吸脱附表征,探究其微观结构与性能之间的关系(图4~8);3.通过苯甲醛和丙二腈的脑文格尔缩合反应,验证催化剂的活性。结论:1.成功合成出高效的磁性NiCo2O4纳米颗粒;2.以脑文格尔缩合反应作为探针反应,发现NiCo2O4具有高催化性能,并且其反应转化率和收率高达99%;3.催化剂具有磁性,易于回收;4.在循环20次后,反应活性不变,说明催化剂具有高稳定性。

关键词： NiCo2O4催化剂尖晶石脑文格尔缩合反应非均相催化

(3S)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮的合成（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第2期17卷 163-170页

作者： Xiao-zhong WANG Xia WANG Ying-qi CHEN li-yan dai Xing-cong li College of Chemical and Biological Engineering Zhejiang University National Centers for Natural Products Research Research Institute of Pharmaceutical Sciences The University of Mississippi

目的:探索合成(3S)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮的新方法。创新点:以常规化工原料D-苯苷氨醇为主要原料,在比较温和的条件下合成重要的药物中间体(3S)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮及其同系物。该方法中的甲... 详细信息

目的:探索合成(3S)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮的新方法。创新点:以常规化工原料D-苯苷氨醇为主要原料,在比较温和的条件下合成重要的药物中间体(3S)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮及其同系物。该方法中的甲基化步骤较常规甲基化步骤减少1当量s-Bu li的用量,更环保和安全。方法:利用D-苯苷氨醇的空间位阻作用,在六元环内酰胺中引入具有特定光学纯度的手性甲基。在甲基化过程中,用叔丁基二甲基氯硅烷对羟基进行保护,以减少仲丁基锂的用量。结论:以工业易得的δ-戊内酯及D-苯苷氨醇为初始原料,探索合成3-甲基-2-哌啶酮类物质的新方法。新方法中对仲丁基锂的消耗量与常规方法有所不同。当羟基受保护时,甲基化1当量六元环内酰胺(化合物7)消耗1.5当量而非2.5当量仲丁基锂,甲基化产物脱掉醇羟基保护基,得到(3S)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮(化合物1)及其非对映异构体(3R)-1-[(R)-2-羟基-1-苯乙基]-3-甲基-2-哌啶酮(化合物8),二者摩尔比为1:2.5。通过重结晶或柱层析的方法可对二者进行完全分离。

关键词：哌啶酮生物碱不对称合成 D-苯甘氨醇醇羟基保护基

Ferromagnetically coupled heterobinuclear Cu(Ⅱ)-Ln(Ⅲ) complexes with N,N'-bis(2-aminoethyl)-oxamido dianion as a bridged ligand

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Chinese Journal of Chemistry 1995年第3期13卷 216-222页

作者： li, yan-Tuan liAO, dai-Zheng JIANG, Zong-Hui WANG, Geng-linDepartment of Chemistry, Nankai University, Tianjin 300071, China

Six novel μ-oxamido heterobinuclear complexes, namely Cu(oxae)Ln(Me2bpy)2-(ClO4)3 (Ln=La, Nd, Gd, Tb, Ho, Er), where oxae denotes N, N'-bis(2-aminoethyl)oxamido dian-ion, Me2bpy is 4,4'-dimethyl-2,2'-bipyridyl, have been synthesized and characterized by elemental analyses, IR, conductivity measurements and electronic spectra. The temperature dependence of the magnetic susceptibility of Cu(oxae)Gd(Me2bpy)2(ClO4)3 has been meaured over the range 4-300 K. The least-squares fit of the experimental susceptibilities yielded J - 1.87 *** observed Gd(Ⅲ)-Cu(Ⅱ) coupling is ferromagnetic. One plausible mechanism that can cause a ferromagnetic coupling between Gd(Ⅲ) and Cu(Ⅱ) is discussed in terms of spin-polarization.

关键词： Copper(II)-lanthanide(III) complex oxamido bridge ferromagnetic coupling.

Emerging trends in the selective production of value-added aromatics

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Science China Chemistry 2025年第1期68卷 15-20页

作者： Yuchao Wu Houliang dai Weisheng yang Yaxing li lichen liu Petrochemical Research Institute Company limited China National Petroleum Corporation Engineering Research Center of Advanced Rare Earth Materials Department of Chemistry Tsinghua University

1 Introduction Aromatics (mainly benzene, toluene, and xylenes, BTX) are essential intermediates in the chemical industry. They are employed in the synthesis of a broad spectrum of chemicals and materials, e.g., various polymers, plastics, resins, solvents, dyes, pharmaceuticals [1]. The manufacturing pathway of BTX mainly includes petroleum reforming of naphtha, coal-to-aromatics, methanol-to-aromatics [2].

关键词：

Manufacture the conducting polymer with light

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Science China Chemistry 2025年第1期68卷 8-9页

作者： yang li Tianyu li yan Ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

关键词：

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China life Sciences 2025年第1期68卷 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun dai Shipeng yan Kun Jiang Bingbing Song He li Maomao Cao Dianqin Sun Fan yang Xinxin yan Shaoli Zhang Yi Teng Qianru li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrendlimited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

关键词： stomach neoplasms precancerous conditions cancer screening cumulative incidence risk stratification

A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： li Ma Cai dai Xingsi Xue Cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy