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我国轨道交通系统不断突破技术创新边界
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作者 孙章 DAI Xiaoyun 《城市轨道交通研究》 北大核心 2026年第2期I0004-I0004,174,共2页
2025年底、“十四五”末,2025年12月26日,随着西延高铁(西安-延安)等数条高速铁路开通运营,中国高铁的营业里程突破5万km,高铁发展再上新台阶;近期开通的沈白高铁(辽宁沈阳-吉林白河)上配备的CR400BF-GS型复兴号智能动车组是专为极端寒... 2025年底、“十四五”末,2025年12月26日,随着西延高铁(西安-延安)等数条高速铁路开通运营,中国高铁的营业里程突破5万km,高铁发展再上新台阶;近期开通的沈白高铁(辽宁沈阳-吉林白河)上配备的CR400BF-GS型复兴号智能动车组是专为极端寒冷环境设计的,它的投入运营进一步提升了我国高铁网络的韧性和适应性;同期在对CR450动车组的测试中创造了惊人的时速453 km的高速度,其交会时速达到了创纪录的896 km。当前,我国正致力于建设更智能、更具韧性的高铁网络。 展开更多
关键词 技术创新 CR400BF-GS型复兴号智能动车组
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审美人类学视域下灵渠的审美化
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作者 阳玉平 《长江师范学院学报》 2026年第1期64-75,共12页
作为世界灌溉工程遗产和国家运河文化建设的重要组成部分,灵渠是秦时期水利技术与水利文化的代表,它沟通湘江与珠江、连接海上丝绸之路,在两千多年的历史进程中为建立统一的多民族国家、文化的交流与互鉴以及地方文化的产生提供了硬件... 作为世界灌溉工程遗产和国家运河文化建设的重要组成部分,灵渠是秦时期水利技术与水利文化的代表,它沟通湘江与珠江、连接海上丝绸之路,在两千多年的历史进程中为建立统一的多民族国家、文化的交流与互鉴以及地方文化的产生提供了硬件基础与软件支撑。依据审美人类学立足于中国文化建设实践的学科建构与理论视域,对灵渠从水利工程到审美对象的转变,实现工具价值到审美价值的转向展开论述,提出灵渠的本质存在与灵渠文化的基本构成为灵渠审美化的基础与条件,而灵渠在历史长河中不断结合具体的历史语境而生活化、景观化和符号化,最终完成了灵渠审美化的完美转身,为地方遗产文化在当代的再生与创新提供了一种建构思路。 展开更多
关键词 审美人类学 灵渠 生活化 景观化 符号化
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Xu Zhihong:Learning From Nature,Inspired by Plants
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作者 HUANG WEI CHEN WENXIN 《China Today》 2026年第1期60-62,共3页
For decades,Xu has been committed to fulfilling the duty and mission of a scientist and educator—diving into the laws of nature,caring deeply for the nation,and earnestly cultivating younger generations.
关键词 cultivating younger generations scientist LAWS nature younger generations EDUCATOR PLANTS laws naturecaring
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Rao Zihe,Luminary in Structural Biology
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作者 CHEN WENXIN 《China Today》 2026年第2期56-58,共3页
From cracking the code of viruses to mentoring the next generation of scientists,the former president of Nankai University has contributed a lot to turning microscopic discoveries into monumental shields for global he... From cracking the code of viruses to mentoring the next generation of scientists,the former president of Nankai University has contributed a lot to turning microscopic discoveries into monumental shields for global health.OVER the past 40 years,one man has distinguished himself through a deep commitment to researching protein structures of high pathogenic viruses,and published numerous significant works in top international scientific journals. 展开更多
关键词 viruses scientific mentoring protein structures structural biology global health cracking code viruses
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“全梳理”概念探讨及梳棉机结构优化
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作者 刘古立 倪远 《纺织器材》 2026年第1期28-33,共6页
为最大化利用梳棉机锡林针布的分梳资源,提高梳棉机工作效率和产能,回顾梳棉机结构和梳理区的技术演变并提出制约梳棉机技术进步的因素;通过分析锡林针布的梳理与怠梳状态,提出了“全梳理”概念,在分析新型高产梳棉机“Ω”梳理区结构... 为最大化利用梳棉机锡林针布的分梳资源,提高梳棉机工作效率和产能,回顾梳棉机结构和梳理区的技术演变并提出制约梳棉机技术进步的因素;通过分析锡林针布的梳理与怠梳状态,提出了“全梳理”概念,在分析新型高产梳棉机“Ω”梳理区结构的基础上构思了“C”字形梳理区结构的“全梳理”梳棉机,并详述其优势及特点。指出:传统梳棉机是“半梳理”状态,新型高产梳棉机通过刺辊、锡林、道夫的位置调整已趋向于“全梳理”状态,但其“Ω”梳理区结构不利于维护保养操作和运行的稳定性;“C”字形梳理区结构的“全梳理”梳棉机,将道夫直径适当缩小并置于刺辊下方,可使纵向梳理区扩大到极致,且方便值车和保养,利于高速高产,可为梳理装备和工艺技术发展提供了多种可能性。 展开更多
关键词 梳棉机 锡林 盖板 道夫 全梳理 梳怠比 “Ω”梳理区 “C”字形梳理区
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Non-equilibrium hydrogel with time-dependent ultrabright fluorescence fabricated by CB-mediated thermodynamic equilibrium host-vip complexes
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作者 Hanren Xu Hongyu An +1 位作者 Qian Wang Da-Hui Qu 《Science China Chemistry》 2026年第2期932-938,共7页
While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these fe... While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications. 展开更多
关键词 fluorescent hydrogel host-vip complexes information encryption dynamic fluorescence
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Engineering stimuli-responsive block copolymers for multimodal bioimaging
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作者 Lizhuang Zhong Ming Liu +3 位作者 Shilong Su Dongxin Zeng Jing Hu Zhiqian Guo 《Chinese Chemical Letters》 2026年第1期116-124,共9页
The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytot... The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytotoxicity.These limitations have catalyzed the development of intelligent stimuli-responsive block copolymers-based bioimaging agents,which was engineered to dynamically respond to endogenous biochemical cues(e.g.,p H gradients,redox potential,enzyme activity,hypoxia environment) or exogenous physical triggers(e.g.,photoirradiation,thermal gradients,ultrasound(US)/magnetic stimuli).Through spatiotemporally controlled structural transformations,stimuli-responsive block copolymers enable precise contrast targeting,activatable signal amplification,and theranostic integration,thereby substantially enhancing signal-to-noise ratios of bioimaging and diagnostic specificity.Hence,this mini-review systematically examines molecular engineering principles for designing p H-,redox-,enzyme-,light-,thermo-,and US/magnetic-responsive polymers,with emphasis on structure-property relationships governing imaging performance modulation.Furthermore,we critically analyze emerging strategies for optical imaging,US synergies,and magnetic resonance imaging(MRI).Multimodal bioimaging has also been elaborated,which could overcome the inherent trade-offs between resolution,penetration depth,and functional specificity in single-modal approaches.By elucidating mechanistic insights and translational challenges,this mini-review aims to establish a design framework of stimuli-responsive block copolymersbased for high fidelity bioimaging agents and accelerate their clinical translation in precise diagnosis and therapy. 展开更多
关键词 STIMULI-RESPONSIVE Block copolymers Molecular engineering Multimodal bioimaging Diagnosis and therapy
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Ion-cluster-optimized microphase separation in shape-memory polydisulfides for enhanced mechanical performance
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作者 Chengyuan Yu Huiyao Lin +5 位作者 Le Li Ruirui Gu Qi Zhang Chenyu Shi Chenchen Zhang Fei Tong 《Chinese Chemical Letters》 2026年第2期494-500,共7页
Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased ... Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased attention due to their unique properties and potential applications in self-healing,shape memory,sensors,and flexible electronics.Here,we develop an ionic cluster-optimized microphase separation strategy to enhance the toughening and energy dissipation capabilities of polydisulfide-based supramolecular polymers.The mechanical properties,including Young's modulus and toughness,are significantly improved by integrating the quadruple H-bonding 2-ureido-4-pyrimidone(UPy)induced microphase separation with iron(III)-to-carboxylate ionic clusters.By combining established chemical approaches with adjustable polymer phase ratios,it is revealed that the synergistic effect of these factors expands the interchain spacing,facilitates the formation of microphase domains,and enhances the tolerance of polythioctic acid-based polymers to external mechanical and thermal stimuli,meeting the practical requirements for industrial plastic applications.Moreover,the UPy-functionalized polymers incorporating iron carboxylate clusters exhibit good one-way shape memory behavior with practical applicability at a relatively low recovery temperature.Our work demonstrates a novel strategy for constructing industrially viable shape memory dynamic SPMs and paves the way for future innovations in developing SPMs. 展开更多
关键词 Polydisulfides Network toughening lonic clusters Microphase separation Shape-memory supramolecular polymers
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Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction
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作者 Fengtao Yu Xiaolong Zhang +5 位作者 Jie Xu Guihong Wu Huiying Lei Zhiwu Yu Jianding Qiu Jianli Hua 《Journal of Energy Chemistry》 2026年第1期284-293,I0007,共11页
As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term... As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term uranium supply but is challenged by ultra-low uranium concentrations and ion interference.To overcome these issues,we design three diketopyrrolopyrrole-based covalent organic frameworks(COFs)via a synergisticπ-extended lock and carboxyl-functionalized anchor molecular engineering strategy.Among them,TPy-DPP-COF features a covalently lockedπ-conjugated structure that enhances planarity,optimizes energy alignment,and minimizes exciton binding energy,thereby promoting charge transfer and suppressing recombination.Concurrently,carboxyl groups enable uranyl-specific coordination and create local electric fields to facilitate charge separation.These features contribute to the outstanding performance of TPy-DPP-COF,which achieves a high uranium adsorption capacity of 16.33 mg g−1 in natural seawater under irradiation,with only 29.3%capacity loss after 10 cycles,surpassing industrial benchmarks.Density functional theory(DFT)calculations and experimental studies reveal a synergistic photocatalysis-adsorption pathway,with DPP units acting as active sites for uranium reduction.This work highlights a molecular design strategy for developing efficient COF-based photocatalysts for practical marine uranium recovery. 展开更多
关键词 DIKETOPYRROLOPYRROLE Covalent organic frameworks Exciton binding energy Photocatalytic uranium extraction Synergistic effect
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Pursuing precise cancer therapy:tumor microenvironment-triggered hydrogen bond self-assembly enables photoreaction transition from type Ⅱ to type Ⅰ
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作者 Mingjie Ye Hanbin Xu +5 位作者 Mengli Liu Mengqi Zhao Shilei Fan Mahmoud Elsayed Hafez Binbin Chen Dawei Li 《Science China Chemistry》 2026年第2期924-931,共8页
Controllable photoreaction transition of photosensitizers(PSs)provides a highly promising approach for achieving efficient photodynamic therapy(PDT).However,tumor microenvironment-triggered phototransition remains a s... Controllable photoreaction transition of photosensitizers(PSs)provides a highly promising approach for achieving efficient photodynamic therapy(PDT).However,tumor microenvironment-triggered phototransition remains a significant challenge and has not yet been reported.In this work,we develop a hydrogen bond self-assembly(HBSA)strategy that is triggered by the acidic tumor microenvironment to enable the photodynamic transition of tetra(4-carboxylphenyl)porphyrin(TCPP)PSs from type Ⅱ to type Ⅰ reactions.Upon self-assembly of TCPP monomers into TCPP assemblies(TCPP-ass),the generated reactive oxygen species shift from singlet oxygen to superoxide anions,which induces caspase-3/GSDME-mediated programmed pyroptosis,enabling rapid and complete solid tumor elimination with minimized adverse effects and enhanced therapeutic efficacy.Crucially,the HBSA process occurs exclusively within tumor cells,and this tumor-specific self-assembly strategy not only utilizes high tissue penetration of TCPP molecular-PSs,but also avoids phototoxicity caused by the formation and accumulation of TCPP-ass nano-PSs in normal tissue,providing an innovative approach for precise cancer therapy. 展开更多
关键词 hydrogen bond self-assembly acidic tumor microenvironment photoreaction transition precise photodynamic therapy
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Unveiling the Anticancer Potential of Urolithin A in Colorectal Cancer:A Systematic Review
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作者 Mariana Francisco Fernando Mendes +1 位作者 Diana Martins Joana Liberal 《Oncology Research》 2026年第2期54-89,共36页
Objectives:Colorectal cancer(CRC)is a major global health burden,and Urolithin A(Uro-A)has emerged as a promising anticancer agent.This systematic review aims to synthesize current in vitro evidence on the anticancer ... Objectives:Colorectal cancer(CRC)is a major global health burden,and Urolithin A(Uro-A)has emerged as a promising anticancer agent.This systematic review aims to synthesize current in vitro evidence on the anticancer effects of Uro-A in CRC,highlighting effective concentration ranges,exposure times,relevant outcomes,and underlying molecular mechanisms.Methods:Following PRISMA 2020 guidelines,a systematic search was conducted in PubMed,Scopus,and Web of Science using the following strategy:(colorectal cancer)AND(urolithin a)OR(3,8-dihydroxy-6H-dibenzo(b,d)pyran-6-one).Eligibility criteria were defined by the PICO framework:(P)in vitro CRC cell models;(I)Uro-A alone or combined treatments;(C)No intervention,vehicle or other treatments;(O)Relevant anticancer outcomes of Uro-A in CRC.Only original,full-text,in vitro studies in English were included.Risk of bias was assessed using ToxRTool.A qualitative synthesis was performed due to the heterogeneity of the included studies.Results:Fifteen studies met inclusion criteria,involving CRC cell lines(Caco-2,HCT-116,HT-29,SW480,SW620)and normal colon fibroblasts(CCD18-Co).Uro-A inhibited CRC cell proliferation,clonogenic growth,cancer stem cells properties,migration,and invasion,and induced cell cycle arrest,apoptosis,autophagy,and senescence,through modulation of key signaling pathways and proteins.Co-treatments with conventional chemotherapeutics and microbiota-derived metabolites showed additive or synergistic effects.Discussion:The findings support UroA’s potential as a preventive or adjuvant agent in CRC treatment.However,preclinical nature of the evidence and methodological heterogeneity hinder clinical extrapolation to in vivo contexts.Human clinical trials are necessary to overcome these limitations.Other:This review was registered in PROSPERO(CRD420251070874)and supported by FCT/MCTES UIDP/05608/2020 and UIDB/05608/2020.Institutional. 展开更多
关键词 Colorectal cancer urolithin A 3 8-dihydroxy-6H-dibenzo(b d)pyran-6-one anticancer effects systematic review
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Gu Binglin,Science Trailblazer and Future-Maker
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作者 CHEN WENXIN 《China Today》 2025年第12期58-60,共3页
The renowned scientist is academician of the Chinese Academy of Sciences,former president of Tsinghua University,and chair of the Tengchong Scientists Forum.ACADEMICIAN of the Chinese Academy of Sciences,former presid... The renowned scientist is academician of the Chinese Academy of Sciences,former president of Tsinghua University,and chair of the Tengchong Scientists Forum.ACADEMICIAN of the Chinese Academy of Sciences,former president of Tsinghua University,and chair of the Tengchong Scientists Forum,Gu Binglin is one of the world’s top physicists and materials scientist,and a pioneer in the field of materials design. 展开更多
关键词 materials design Tsinghua University Tengchong Scientists Forum materials scientist ACADEMICIAN PHYSICIST
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长期保护性耕作对玉米生育期土壤真菌群落的影响
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作者 徐莹莹 王宇先 +4 位作者 杨慧莹 高盼 张巩亮 刘玉涛 申惠波 《玉米科学》 北大核心 2025年第7期78-87,98,共11页
为全面了解土壤真菌群落整体特征,明确长期保护性耕作对土壤真菌群落多样性、结构组成及功能的影响,基于9年长期定位试验,设置免耕秸秆覆盖还田(NTS)、深松秸秆还田(STS)两种保护性耕作措施及传统耕作(CK)共3种处理,采用高通量测序技术... 为全面了解土壤真菌群落整体特征,明确长期保护性耕作对土壤真菌群落多样性、结构组成及功能的影响,基于9年长期定位试验,设置免耕秸秆覆盖还田(NTS)、深松秸秆还田(STS)两种保护性耕作措施及传统耕作(CK)共3种处理,采用高通量测序技术,监测玉米关键生育期不同处理下土壤真菌群落特征。结果表明,与CK相比,STS处理使吐丝期真菌群落丰富度显著下降28.44%,拔节期、吐丝期和成熟期群落多样性分别下降42.90%、32.29%和12.14%;NTS处理群落丰富度与CK差异不显著。保护性耕作显著降低了赤霉属(Gibberella)、镰刀菌属(Fusarium)等病害类群的相对丰度,提高了担子菌门(Basidiomycota)、被孢菌属(Mortierella)等有益类群的相对丰度,且STS处理效果更佳。从功能来看,保护性耕作显著降低了病理营养类型群体的相对丰度,提高了腐生型类群的相对丰度。此外,STS处理还显著提高了腐生-共生型类群的相对丰度。综上,长期深松秸秆还田更有利于优化土壤真菌群落。 展开更多
关键词 玉米 生育期 保护性耕作 土壤真菌群落 真菌群落功能
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水肥一体化模式下施氮量对玉米根际土壤固氮菌群落及生长的调控
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作者 徐莹莹 王宇先 +4 位作者 高盼 杨慧莹 张巩亮 申惠波 刘玉涛 《福建农业学报》 北大核心 2025年第6期637-648,共12页
【目的】探讨水肥一体化模式下施氮量对玉米根际土壤固氮菌群落及生长的调控效应。【方法】设置5种追肥施氮量,分别为不施氮(N0:0 kg·hm^(-2))、低氮(N1:98 kg·hm^(-2),70%N)、中氮(N2:140 kg·hm^(-2),100%N)、高氮(N3:1... 【目的】探讨水肥一体化模式下施氮量对玉米根际土壤固氮菌群落及生长的调控效应。【方法】设置5种追肥施氮量,分别为不施氮(N0:0 kg·hm^(-2))、低氮(N1:98 kg·hm^(-2),70%N)、中氮(N2:140 kg·hm^(-2),100%N)、高氮(N3:182 kg·hm^(-2),130%N)和过量氮(N4:210 kg·hm^(-2),150%N),利用高通量测序技术比较不同施氮量下玉米根际土壤固氮菌群落多样性及结构组成差异性,并结合土壤氮素及玉米生长指标,阐释施氮量的调控机制。【结果】施氮显著提高了各生育时期根际土壤氮素含量,并促进了玉米生物量和氮素的积累,N2表现最佳。固氮菌整体α多样性随施氮量增加呈先下降后上升再下降趋势,N2提高了α多样性,而N1和N4降低了多样性。施氮显著影响了固氮菌群落结构,尤其在拔节期和开花期,样本明显分离。菌群组成显示,施氮显著提高了土壤有益微生物慢生根瘤菌属(Bradyrhizobium)的丰度,同时N2提高了促生菌未分类伯克氏菌目(unclassified_o__Burkholderiales)的相对丰度。关联网络分析表明,N2的模块化指数等拓扑参数上调,表明菌群结构更稳定。偏最小二乘路径模型进一步揭示,施氮量通过土壤氮组分间接正向调控玉米生长。【结论】追肥施氮量140 kg·hm^(-2)(N2)时优化了根际土壤生态环境,增强固氮菌群落稳定性并促进玉米生长,建议作为半干旱区玉米水肥一体化种植参考施氮量。 展开更多
关键词 玉米 水肥一体化 施氮量 根际土壤 固氮菌群落
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基于温和预处理玉米秸秆的酶解糖化工艺研究
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作者 张欢欢 林钰程 +4 位作者 王圆圆 赵世强 杜朝军 赵子高 常春 《可再生能源》 北大核心 2025年第2期143-151,共9页
秸秆类生物质的预处理和酶解是实现其高值化转化、利用的关键技术之一。文章以玉米秸秆为原料,对甲酸、亚氯酸钠和碱性过氧化氢预处理方法进行了研究和比较。采用扫描电镜、X射线衍射和傅里叶变换红外光谱等方法对预处理前后玉米秸秆的... 秸秆类生物质的预处理和酶解是实现其高值化转化、利用的关键技术之一。文章以玉米秸秆为原料,对甲酸、亚氯酸钠和碱性过氧化氢预处理方法进行了研究和比较。采用扫描电镜、X射线衍射和傅里叶变换红外光谱等方法对预处理前后玉米秸秆的组成、形貌、晶体结构和官能团进行了分析。经过甲酸、亚氯酸钠和碱性过氧化氢预处理后,木质素去除率分别为66.71%,97.12%和91.88%,酶解率分别达到63.26%,71.83%和95.14%。在纤维素酶添加量为19.6 FPU/g,木聚糖酶添加量为35.44 IU/g,吐温80添加量为20.96 mg/g的条件下,碱性过氧化氢预处理后玉米秸秆的预测酶解率为95.57%,实际酶解率为94.42%。高固体酶解的最佳补料策略是初始底物浓度为8%,在6,12,24 h分别添加4%的底物,酶解120 h后,酶解率达到87.57%。 展开更多
关键词 玉米秸秆 预处理 高固酶解 分批补料
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生物质基羧甲基纤维素制备与应用新进展
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作者 张淏龙 林钰程 +4 位作者 张赛 侯刘涛 张玉涛 韩秀丽 常春 《现代化工》 北大核心 2025年第4期37-42,共6页
从制备羧甲基纤维素(carboxymethyl cellulose, CMC)的生物质原料出发,介绍了制备CMC的非粮生物质原料。根据CMC制备工艺过程,分别对生物质纤维素提取、碱化和醚化工艺、CMC表征及改性进行了综述。使用绿色溶剂预处理是提取纤维素的发... 从制备羧甲基纤维素(carboxymethyl cellulose, CMC)的生物质原料出发,介绍了制备CMC的非粮生物质原料。根据CMC制备工艺过程,分别对生物质纤维素提取、碱化和醚化工艺、CMC表征及改性进行了综述。使用绿色溶剂预处理是提取纤维素的发展方向;碱化、醚化工艺采用溶液法有助于制备高性能产品,通过工艺创新可制备高取代度、高黏度CMC;进一步采用物理、化学改性可提高产品性能。在此基础上,综述了CMC在农业、环境、医疗、新能源等领域的创新应用,分析了CMC应用新趋势,展望了CMC在不同领域的应用前景。 展开更多
关键词 生物质 羧甲基纤维素 取代度 改性 高值化利用
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柳蒿多酚的提取工艺优化及其抗氧化研究 被引量:2
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作者 崔艳艳 朱金鑫 +5 位作者 郭明坤 张敏景 栾秀殊 刘奕彤 裴世春 何文兵 《饲料工业》 北大核心 2025年第9期99-106,共8页
研究旨在从柳蒿中提取并纯化多酚类化合物,分析其理化性质及结构,并探究其对油脂的抗氧化活性。利用单因素试验结合响应面优化,确定柳蒿多酚的最佳提取工艺,采用紫外光谱(UV)和傅里叶变换红外光谱(FT-IR)分析其结构,并通过Schaal烘箱法... 研究旨在从柳蒿中提取并纯化多酚类化合物,分析其理化性质及结构,并探究其对油脂的抗氧化活性。利用单因素试验结合响应面优化,确定柳蒿多酚的最佳提取工艺,采用紫外光谱(UV)和傅里叶变换红外光谱(FT-IR)分析其结构,并通过Schaal烘箱法评估柳蒿多酚对油脂的抗氧化效果。结果表明:柳蒿多酚的最佳提取工艺为料液比1∶40 g/mL,乙醇体积分数72%,超声温度60℃,超声时间30 min。此条件下柳蒿多酚提取率为4.87%,与多酚最大提取率预测值的相对误差为0.03359%。纯化后的柳蒿多酚总酚含量(735.70±28.46)mg/g,总黄酮含量(324.21±13.84)mg/g,平均粒径(544.07±46.34)nm,平均Zeta电位(-23.89±1.99)mV。UV和FT-IR结果显示,柳蒿多酚含有多酚类化合物特征结构,主要为绿原酸成分。油脂抗氧化结果表明,柳蒿多酚能够延缓油脂中酸价(AV)、过氧化值(POV)和2-硫代巴比妥酸值(TBA)的上升,对植物油脂和动物油脂均表现出一定的脂质抗氧化作用。 展开更多
关键词 响应面法 柳蒿多酚 提取工艺 结构表征 抗氧化
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生物质水热碳化制备黑色母粒着色剂研究进展
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作者 张帅飞 陈红胜 +4 位作者 朱宁博 陈俊英 李攀 李慧星 陈玮 《河南化工》 2025年第1期1-4,12,共5页
传统黑色母粒着色剂工业生产方法是以合成烃和天然气为原料,通过热解生产,其生产成本及能耗高,环境污染严重。介绍了生物质水热碳化制备黑色母粒着色剂的现状,与传统热解技术相比,水热碳化能耗较低且原料不需干燥。利用生物质原料水热... 传统黑色母粒着色剂工业生产方法是以合成烃和天然气为原料,通过热解生产,其生产成本及能耗高,环境污染严重。介绍了生物质水热碳化制备黑色母粒着色剂的现状,与传统热解技术相比,水热碳化能耗较低且原料不需干燥。利用生物质原料水热碳化可低成本地生产黑色母粒着色剂,是降低黑色母粒着色剂生产成本的关键环节,探讨了水热温度、水热时间、原料粒径等不同水热碳化条件对制备黑色母粒着色剂的影响,为生物质的高值化利用及黑色母粒着色剂的低成本制备提供参考。 展开更多
关键词 生物质 水热碳化 生物炭 黑色母粒着色剂
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Energy transfer enhanced photocatalytic hydrogen evolution in organic heterostructure nanoparticles via flash nanoprecipitation processing 被引量:1
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作者 Miaojie Yu Weiwei Zhang +4 位作者 Xueyan Liu Guohui Zhao Jun Du Yongzhen Wu Wei-Hong Zhu 《Green Energy & Environment》 2025年第2期390-398,共9页
Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a b... Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration. 展开更多
关键词 Polymer photocatalysts NANOPARTICLES Hydrogen evolution Forster resonance energy transfer
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不同年龄贵乾半细毛羊粪便养分和重金属含量及微生物指标的测定
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作者 郭振刚 吴瑛 +2 位作者 吴萍 吴道全 宋德荣 《家畜生态学报》 北大核心 2025年第9期104-108,共5页
为了解贵乾半细毛羊养殖生产中粪污污染现状,试验选择健康的贵乾半细毛羊20只,分为成年羊组和育成羊组,每组公母羊各5只,分别测定了进食饮水量、粪尿排泄量及粪便中养分和重金属含量。结果表明,贵乾半细毛羊进食饮水量和粪尿排泄量平均... 为了解贵乾半细毛羊养殖生产中粪污污染现状,试验选择健康的贵乾半细毛羊20只,分为成年羊组和育成羊组,每组公母羊各5只,分别测定了进食饮水量、粪尿排泄量及粪便中养分和重金属含量。结果表明,贵乾半细毛羊进食饮水量和粪尿排泄量平均分别为3.52 kg/d、1.12L/d、1.19kg/d和0.60kg/d,成年羊的进食鲜质量、粪便鲜质量均高于育成羊,但差异不显著(P<0.05),而饮水量和尿液量则显著低于育成羊(P>0.05);在养分含量方面,贵乾半细毛羊粪便有机质(OM)含量平均达74.15%,成年羊全钾(TK)含量低于育成羊,差异不显著(P>0.05),但成年羊的有机质(OM)、全氮(TN)、全磷(TP)、氨态氮(NH_(4)^(+)-N)和硝态氮(NO_(3)^(-)-N)显著高于育成羊(P<0.05);在重金属含量方面,贵乾半细毛羊粪便中未检出总砷(As)和总镉(Cd),成年羊的总铜(Cu)、总锌(Zn)、总汞(Hg)、总铅(Pb)和总铬(Cr)高于育成羊,但仅Zn显著高于育成羊(P<0.05),达64.25g/kg,其余指标差异不显著(P>0.05);此外,不论是成年羊还是育成羊,其粪便中的蛔虫卵均未检出,死亡率达100%,而成年羊粪便中大肠杆菌群数为15.28MPN/g,高于育成羊,但差异不显著(P>0.05)。试验结果为充分了解贵乾半细毛羊新品种养殖污染现状、科学配制饲料配方和制定产业发展规划等提供了依据。 展开更多
关键词 贵乾半细毛羊 粪便 养分 重金属 粪污污染
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