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金沙江干热河谷脆弱生态系统植被恢复及可持续生态农业模式

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水土保持学报 2003年第5期17卷 19-22页

作者：纪中华刘光华段曰汤沙毓沧李建增云南农业科学院热带亚热带经济作物研究所云南元谋651300

金沙江河谷脆弱生态系统具有:干旱程度加剧,土壤凋萎湿度(PWP)长达7～8个月,使许多植物无法生长;水热矛盾突出;水土流失严重;人为破坏频繁;植物群落破坏容易,恢复难;土壤胀缩性高而不利于作物生长等特点。其中水分短缺是脆弱生态系统最... 详细信息

金沙江河谷脆弱生态系统具有:干旱程度加剧,土壤凋萎湿度(PWP)长达7～8个月,使许多植物无法生长;水热矛盾突出;水土流失严重;人为破坏频繁;植物群落破坏容易,恢复难;土壤胀缩性高而不利于作物生长等特点。其中水分短缺是脆弱生态系统最严重的问题。因此,植被恢复以及可持续发展模式的建立应按水分来源划分为不同的建设系统,即:雨养生态系统,保水补灌系统,适水灌溉系统。针对不同系统,从整体性、紧迫性、持久性、创新性、多样性、高效性、层次性角度提出金沙江干热河谷退化生态系统植被恢复及可持续生态农业模式。即生物立体共生的生态农业模式、物质循环利用的生态农业模式、生态环境综合治理模式、资源开发利用综合模式、综合发展与全面建设的生态农业模式。

关键词：脆弱生态系统植被恢复与生态农业模式金沙江干热河谷

Synthesis of 7-Methylbenzo[b]furanolactol from m-Cresol via Willgerodt-Kindler reaction

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Synthesis of 7-Methylbenzo[b]furanolactol from m-Cresol via ...

Nitrogen addition promotes soil carbon accumulation globally

中国化学会第四届有机化学学术会议

作者： WANG, Chen-Ying CHEN, jing-Bo ji, Yan-hua liu, ji-Kai ZHANG, Hong-Bin (State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204) (School of Pharmacy, Center for Advanced Studies of Medicinal and Organic Chemistry, Yunnan University, Kunming 650091)

＜正＞Benzofuran-2（3H）-ones are a naturally-occurring and biologically interesting class of heterocycles. In 1997, Kalinin and co-workers synthesized benzo[b]furan-2（3）-ones via a new LDA mediated O→C carbamoyl migration to obtain a general and efficient route to ary1 acetamides, precursors to the benzo- and naphtho-furanones, and then compound 4 serves as a intermediate for a short synthesis of naturally-occurring benzofuranolactol 5 isolated from several Heienium species via 4 steps in 42%-56% overall yield. Here we wish to report a new route for the synthesis of 7-methylbenzofuranlactol obtained from m-cresol via 7 steps in 23% overall yield.

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Science China Life Sciences 2025年第1期 284-293页

作者： Xuemei Yang Suhui Ma Erhan huang Danhua Zhang Guoping Chen jiangling Zhu Chengjun ji Biao Zhu Lingli liu jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

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柴油机排气微粒可溶有机成份及苯并(a)芘的研究

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吉林工业大学学报 1989年第4期19卷 28-33页

作者：彭美春季雨张华刘巽俊吉林工业大学

本文用溶剂萃取法和热重法测量了柴油机排气微粒中可溶有机成份(SOF),研究了SOF随发动机负荷的变化关系,并比较了溶剂萃取法与热重法所得结果。还对微粒中的苯并(a)芘进行了定量分析。

关键词：柴油机排气微粒可溶有机成份 BaP

有机–无机肥配施比例对双季稻田土壤质量的影响

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植物营养与肥料学报 2017年第4期23卷 904-913页

作者：吕真真吴向东侯红乾冀建华刘秀梅刘益仁江西省农业科学院土壤肥料与资源环境研究所江西南昌330200 国家红壤改良工程技术研究中心江西南昌330200 江西省水利科学研究院江西南昌330029

【目的】利用江西省稻田土壤质量演变定位监测试验为平台,系统分析长期不同施肥措施下土壤质量状况,明确提升红壤性双季稻田土壤质量的优化施肥措施。【方法】长期定位试验设置8个处理,分别为不施肥处理(CK),施磷钾肥处理(PK),施氮磷肥... 详细信息

【目的】利用江西省稻田土壤质量演变定位监测试验为平台,系统分析长期不同施肥措施下土壤质量状况,明确提升红壤性双季稻田土壤质量的优化施肥措施。【方法】长期定位试验设置8个处理,分别为不施肥处理(CK),施磷钾肥处理(PK),施氮磷肥处理(NP),施氮钾肥处理(NK),施氮磷钾肥处理(NPK),施70%化肥+30%有机肥处理(70F+30M),施50%化肥+50%有机肥处理(50F+50M),施30%化肥+70%有机肥处理(30F+70M),于2012年晚稻收获后测定2个土壤物理性质指标(容重和总孔隙度)、7个基础化学性质指标(有机质、全氮、全磷、碱解氮、有效磷、速效钾和p H值)及3个生物学性质指标(细菌、真菌和放线菌数量),分析长期不同施肥对各土壤性质的影响,并运用主成分分析对各处理土壤质量进行综合评分,最后将综合得分进行聚类分析,以评价长期不同施肥措施对红壤性双季稻田土壤质量的影响。【结果】经28年连续不同施肥处理后,各土壤性质在处理间均产生显著差异,但各土壤性质在处理间的变化趋势并不完全一致。化肥配施有机肥处理较化肥处理土壤容重降低12.7%~20.6%,土壤孔隙度增加2.3%~17.4%,有机质增加22.5%~41.8%,全氮和碱解氮分别提高9.8%~20.9%和11.1%~30.3%,全磷和有效磷分别提高11.1%~71.7%和1.31~1.75倍,p H值提高0.19~0.48个单位;主成分分析方法将原12个土壤性质指标降维、提取出2个主成分,反映了原信息量的87.4%,有机质、容重、真菌、全氮、有效磷、放线菌、总孔隙度、细菌、全磷和碱解氮在第一主成分上有较高载荷值,p H值和速效钾在第二主成分上有较高载荷;各施肥处理下土壤质量综合水平高低排序为:30%F+70M>50F+50M>70F+30M>NPK>NP>NK>PK>CK;聚类分析方法将长期不同施肥制度下稻田土壤质量划分为一级(30F+70M),二级(50F+50M、70F+30M),三级(NPK、NP),四级(NK、PK、CK)4个等级。【结论】与单施化肥相比,有机无机配施可有效增加土壤养分含量,改善土壤物理性质,缓解土壤酸化,提高土壤微生物数量,是提高红壤性双季稻田土壤质量的有效施肥措施。

关键词：长期施肥红壤性水稻土土壤质量主成分分析聚类分析

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一种交通流状态分析模型

上海交通大学学报 2003年第11期37卷 1776-1779,1787页

作者：郑兴宇牛世继刘中华刘允才上海交通大学电子信息与电气工程学院上海200030

从经典的车辆跟驰模型出发,考虑车流的宏观特征,提出了可以定量描述路段交通流速度与密度关系的理论计算模型,经过与DelCastillo等提出的典型的平衡速度、密度关系图的对比,验证了该模型的正确性.与Blunden等提出的流量、行程时间关系... 详细信息

从经典的车辆跟驰模型出发,考虑车流的宏观特征,提出了可以定量描述路段交通流速度与密度关系的理论计算模型,经过与DelCastillo等提出的典型的平衡速度、密度关系图的对比,验证了该模型的正确性.与Blunden等提出的流量、行程时间关系模型进行比较,从理论上说明了该模型的优越性.提出了"交通流健康、不健康状态"的概念,并给出了定量的区分标准,进一步说明了该模型的理论意义和实用价值.

关键词：交通流跟驰流量

CAF-derived exosome-miR-3124-5p promotes malignant biological processes in NSCLC via the TOLLIP/TLR4-MyD88-NF-κB pathway

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Oncology research 2025年第1期33卷 133-148页

作者： Tao Sun Qinghua Song hua liu Department of Respiratory and Critical Care Medicine Affiliated Hospital of Nantong University Medical School of Nantong University Nantong 226001 China. Department of Emergency The People's Hospital of Rugao Nantong 226500 China. Department of Haematology The People's Hospital of Rugao Nantong 226500 China.

Background:Lung cancer is a life-threatening disease that occurs worldwide, but is especially common in China. The crucial role of the tumour microenvironment (TME) in non-small cell lung cancer (NSCLC) has attracted recent attention. Cancer-associated fibroblasts (CAFs) are the main factors that contribute to the TME function, and CAF exosomes are closely linked to NSCLC.Methods:The expression levels of miR-3124-5p and Toll-interacting protein (TOLLIP) were analysed by bioinformatics prediction combined with RT-qPCR/Western Blot detection. Fibroblasts were isolated and identified from clinical NSCLC tissues. Transmission electron microscopy and Western Blot were used to identify exosomes from these cells. Changes in proliferation (CCK-8 and clone formation), migration (wound healing), and invasion (transwell) of NSCLC cells were measured. The Luciferase reporter test was applied to clarify the binding of miR-3124-5p to TOLLIP. The TOLLIP/TLR4/MyD88/NF-κB pathway proteins were determined using Western blot analysis.Results:MiR-3124-5p is overexpressed in clinical tissues and cells of NSCLC. MiR-3124-5p was dramatically enriched in CAF-derived exosomes. Cellular experiments revealed that CAFs delivered miR-3124-5p into NSCLC cells via exosomes, stimulating cancer cell progression. MiR-3124-5p acted as a sponge to negatively regulate TOLLIP expression, which activated the TLR4/MyD88/NF-κB axis to promote the occurrence and development of NSCLC. Functional salvage tests were performed to determine whether CAF-exosome-derived miR-3124-5p plays a pro-cancer role in NSCLC by affecting the TOLLIP signalling pathway.Conclusions:These results provide an interesting direction for the diagnosis and therapy of NSCLC.

关键词： Cancer-associated fibroblasts (CAFs) Exosomes Non-small cell lung cancer (NSCLC) Toll-interacting protein (TOLLIP) miR-3124-5p

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硫酰氟对德国小蠊熏杀效果观察

天津医科大学学报 1999年第4期5卷 28-29页

作者：纪伟华刘永超天津医科大学寄生虫教研室

目的 :观察硫酰氟对德国小蠊成虫和卵的熏杀效果。方法 :采用玻璃缸熏蒸法和玻璃瓶药膜法检测熏杀剂的最佳浓度。结果 :低浓度 ( 2 5～ 65g/m3 )下 ,45min内能击倒全部试虫 ,且无复苏。结论 :硫酰氟对德国小蠊成虫的杀灭效果好 ,可达到... 详细信息

目的 :观察硫酰氟对德国小蠊成虫和卵的熏杀效果。方法 :采用玻璃缸熏蒸法和玻璃瓶药膜法检测熏杀剂的最佳浓度。结果 :低浓度 ( 2 5～ 65g/m3 )下 ,45min内能击倒全部试虫 ,且无复苏。结论 :硫酰氟对德国小蠊成虫的杀灭效果好 ,可达到根除 ,杀卵效力高于溴氰菊酯。

关键词：硫酰氟熏杀德国小蠊药理

Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： Yi jing Xin-Ran liu Xing-hua Wang Hui Han Sha-Sha Liang Xi-Meng Chen Dong-Hui Wei Lai-Sheng Wang Xue-Nian Chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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