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珠三角森林城市群建设特点与高品质发展策略

林草资源研究 2024年第2期 149-154页

作者：陈晗杨开良王杰秦立厚国家林业和草原局林草调查规划院北京100714

森林城市群是区域生态建设和发展的新模式,珠三角森林城市群是国内具有良好发展基础的森林城市群。但目前,珠三角森林城市群仍存在生态斑块破碎化、城市间城乡间绿化较为薄弱等问题,亟需进一步缓解区域生态问题、提升区域生态品质。结... 详细信息

森林城市群是区域生态建设和发展的新模式,珠三角森林城市群是国内具有良好发展基础的森林城市群。但目前,珠三角森林城市群仍存在生态斑块破碎化、城市间城乡间绿化较为薄弱等问题,亟需进一步缓解区域生态问题、提升区域生态品质。结合森林城市群、森林城市建设背景,分析珠三角森林城市群的发展基础和特点、森林城市的建设特征,以及珠三角区域面临的生态问题,探讨珠三角森林城市群高品质发展策略。森林城市群建设是区域尺度生态建设的有效途径,珠三角森林城市群建设为推动全国不同区域的森林城市群建设提供了研究案例。

关键词：森林城市群珠三角高品质发展

Hydrogeochemical Characteristics of Fluorine in Shallow Groundwater of Tongshan Area

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Journal of China University of Mining and Technology 2005年第2期15卷 110-113页

作者： ZHOULai FENGQi-yan lihou-yao SchoolofEnvironmentandSpatialInformatics ChinaUniversityofMining＆TechnologyXuzhouJiangsu221008China JiangsuDepartmentofLand＆Resources NanjingJiangsu210018China

Tongshan area,a part of the floodplain of the abandoned Huanghe River, is one of the popular endemic fluorosis areas in East China. One of the reasons is high concentration of fluorine in shallow groundwater. Test results of 36 groundwater samples show that fluorine concentration in shallow groundwater is 0.18–6.7 mg/L and 50 % of the samples exceed the Chinese drinking water quality standard. There exists a significant negative correlation in content between Ca2+ and F - . The correlations between fluorine concentration and other cations (for example Na+, K+, Mg2+) are not significant. The content of dissolved fluorine from the flooding sediments of the Huanghe River that varying from 5.6 mg/kg to 15.2 mg/kg plays an important role in forming the high fluorine groundwater. Usually, the dissolved fluorine content in silt is much higher than that in silty clay and clay. According to the geological investigation fluorine content in deep groundwater (over 60 m) is less than 1.0 mg/L and suitable for drinking, so it is an effective measure to prevent endemic fluorosis by extracting deep groundwater in disease areas.

关键词： shallow groundwater fluorine flooding sediment dissolved fluorine Tongshan area

Screening difFerentially expressed genes in mouse hepatocarcinoma ascites cell line with high potential of lymphatic metastasis

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World Journal of Gastroenterology 2005年第12期11卷 1837-1842页

作者： Xiao-NanCui Jian-WuTang lihou BoSong LiLi Ji-WeiLiu DepartmentofOncology the1stAffilitateHospitalofDalianMedicalUniversityDalian116011LiaoningProvinceChina DepartmentofPathology DalianMedicalUniversityDalian116027LiaoningProvinceChina

AIM: To screen genes differentially expressed in mouse hepatocarcinoma ascites cell line with high potential of lymphatic ***: A subtracted cDNA library of mouse hepatocarcinoma cell line with high potential of lymphatic metastatic Hca-F and its synogenetic cell line Hca-P with a low metastatic potential was constructed by suppression subtracted hybridization(SSH) method. The screened clones of the subtracted library were sequenced and GeneBank homology search was ***: Fourteen differentially expressed cDNA fragments of Hca-F were obtained with two novel ***: SSH is a useful technique to detect differentially expressioned genes and an effective method to clone novel genes.

关键词： Suppression subtracted hybridization Liver neoplasm Lymphogenous metastasis

Uncertainties in above ground tree biomass estimation

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Journal of Forestry Research 2021年第5期32卷 1989-2000页

作者： lihou Qin Shengwang Meng Guang Zhou Qijing Liu Zhenzhao Xu College of Forestry Beijing Forestry UniversityBeijing 100083People’s Republic of China Qianyanzhou Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China Jiangxi Academy of Forestry Nanchang 330022People’s Republic of China

Models of above-ground tree biomass have been widely used to estimate forest biomass using national forest inventory ***,many sources of uncertainty affect above-ground biomass estimation and are challenging to *** this study,the uncertainties associated with the measurement error in independent variables(diameter at breast height,tree height),residual variability,variances of the parameter estimates,and the sampling variability of national inventory data are estimated for five above-ground biomass *** results show sampling variability is the most significant source of *** measurement error and residual variability have negligible effects on forests above-ground biomass ***,a reduction in the uncertainty of the sampling variability has the greatest potential to decrease the overall *** power model containing only the diameter at breast height has the smallest *** findings of this study provide suggestions to achieve a trade-off between accuracy and cost for above-ground biomass estimation using field work.

关键词： Above-ground biomass Measurement error Residual variability Parameter estimates Sampling variability

Identify lymphatic metastasis-associated genes in mouse hepatocarcinoma cell lines using gene chip

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World Journal of Gastroenterology 2005年第10期11卷 1463-1472页

作者： BoSong Jian-WuTang BoWang Xiao-NanCui lihou LuSun Li-MinMao Chun-HuiZhou YueDu Li-HuiWang Hua-XinWang Ren-ShuZheng LeiSun DepartmentofPathology DalianMedicalUniversityDalian116027LiaoningProvinceChina ShanghaiJingtaiBiotechnologyCorporationLtd Shanghai200000China

AIM: In order to obtain lymphogenous metastasisassociated genes, we compared the transcriptional profiles of mouse hepatocarcinoma cell lines Hca-F with highly lymphatic metastasis potential and Hca-P with low lymphatic metastasis ***: Total RNA was isolated from Hca-F and Hca-P cells and synthesized into double-stranded cDNA. In vitro transcription double-stranded cDNA was labeled with biotin (i.e. biotin-labeled cRNA, used as the probe). The cRNA probes hybridized with Affymetrix GeneChip() MOE430A (containing 22 690 transcripts, including 14 500 known mouse genes and 4 371 ESTs) respectively and the signals were scanned by the GeneArray Scanner. The results were then analyzed by ***: Out of the 14 500 known genes investigated,110 (0.8%) were up regulated at least 23 fold. Among the total 4 371 ESTs, 17 ESTs (0.4%) (data were not presented) were up regulated at least 23 fold. According to the Gene Ontology and TreeView analysis, the 110genes were further classified into two groups: differential biological process profile and molecular function ***: Using high-throughput gene chip method,a large number of genes and their cellular functions about angiogenesis, cell adhesion, signal transduction, cell motility, transport, microtubule-based process, cytoskeleton organization and biogenesis, cell cycle, transcription,chaperone activity, motor activity, protein kinase activity,receptor binding and protein binding might be involved in the process of lymphatic metastasis and deserve to be used as potential candidates for further *** D1, Fosl1, Hsp47, EGFR and AR, and Cav-1 are selected as the possible candidate genes of the metastatic phenotype, which need to be validated in later *** (data were not presented) might indicate novel genes associated with lymphatic metastasis. Validating the function of these genes is helpful to identify the key or candidate gene/pathway responsible for lymphatic m

关键词： Hepatocarcinoma Lymphatic metastasis Cell lines Hca-F and Hca-P Gene chip

Construction and selection of subtracted cDNA library of mouse hepatocarcinoma cell lines with different lymphatic metastasis potential

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World Journal of Gastroenterology 2004年第16期10卷 2318-2322页

作者： lihou Jan-WuTang Xiao-NanCui BoWang BoSong LeiSun DepartmentofPathology DalianMedicalUniversityDalian116027LiaoningProvinceChina

AIM: In order to elucidate the molecular mechanism of lymphatic metastasis of hepatocarcinoma, we detected the difference of gene expression between mouse hepatocarcinoma cell lines Hca-F and Hca-P with different lymphatic metastasis ***: cDNA of Hca-F cells was used as a tester and cDNA of Hca-P cells was used as a driver, cDNAs highly expressed in Hca-F cells were isolated by the suppression subtractive hybridization (SSH) method. The isolated cDNA was cloned into T/A cloning vector. The ligation products were transformed into DH5 α competent cells. Individual dories were randomly selected and used for PCR *** DNA from positive clones was isolated for ***: There were 800 positive clones in amplified subtracted cDNA library. Random analysis of 160 clones with PCR showed that 95% of the clones contained 100-700 bp inserts. Analysis of 20 sequenced cDNA clones randomly picked from the SSH library revealed 4 known genes(mouse heat shock protein 84 ku, DNA helicase, ribosomal protein S13 ,ethanol induced 6 gene) and 3 expressed sequence tags (ESTs). Four cDNAs showed no homology and presumably represent novel ***: A subtracted cDNA library of differentially expressed genes in mouse heptocarcinoma cell lines with different lymphatic metastasis potential was successfully constructed with SSH and T/A cloning techniques. The library is efficient and lays a solid foundation for searching new lymphatic metastasis related genes. The expression of mouse heat shock protein gene, DNA helicase and other 4 novel gene may be different between mouse heptocarcinoma cell lines with different lymphatic metastasis potential.

关键词： cDNA图书馆肝癌老鼠癌细胞系统淋巴腺转移肿瘤

受控振动系统时滞依赖稳定性判据的LMI方法

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应用力学学报 2006年第3期23卷 410-415页

作者：潘颖石嵘刘立厚上海工程技术大学上海200336

针对带有不确定性时滞的振动控制系统,引入改进的二向量内积的上确界,对Lyapunov导数进行合理放大,提出了一种新的时滞依赖鲁棒性稳定准则。根据这种新的判别方法,受控振动系统的最大时滞量可以通过Matlab控制工具箱LMI(线性矩阵不等式... 详细信息

针对带有不确定性时滞的振动控制系统,引入改进的二向量内积的上确界,对Lyapunov导数进行合理放大,提出了一种新的时滞依赖鲁棒性稳定准则。根据这种新的判别方法,受控振动系统的最大时滞量可以通过Matlab控制工具箱LMI(线性矩阵不等式)得到。讨论了单自由度系统中最大时滞随系统参数的变化情况及多自由度系统中控制器最优权值R的确定。算例结果表明,在允许时滞范围内,经典的LQR控制器可以收到令人满意的效果。

关键词：稳定性时滞依赖不确定时滞振动系统

光合特性与长白山阔叶红松林主要树种凋落叶分解速率的关系

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北京林业大学学报 2023年第11期45卷 11-22页

作者：张潇秦立厚刘琪璟北京林业大学林学院北京100083 国家林业和草原局调查规划设计院北京100714

【目的】阐明长白山阔叶红松林乔木树种和灌木树种凋落叶分解之间的差异,探讨光合参数与植物凋落叶分解速率之间的关系,为揭示叶片经济学谱的普适性提供依据。【方法】以19个乔木树种和11个灌木树种作为研究对象,采用网袋法做分解试验,2... 详细信息

【目的】阐明长白山阔叶红松林乔木树种和灌木树种凋落叶分解之间的差异,探讨光合参数与植物凋落叶分解速率之间的关系,为揭示叶片经济学谱的普适性提供依据。【方法】以19个乔木树种和11个灌木树种作为研究对象,采用网袋法做分解试验,2019年10月26日布设分解袋,2020年4月26日、6月26日、8月26日、10月26日回收分解袋;通过Olson负指数衰减模型拟合分解系数,使用Li-6400便携式光合测定仪测定原位活体叶片的光响应曲线,拟合光合参数,分析相关性,并进行回归分析。【结果】(1)乔木树种中,红松分解系数最小(0.24),黄檗最大(1.05);灌木树种中,毛榛分解系数最小(0.52),瘤枝卫矛最大(1.63);灌木树种分解系数总体高于乔木树种(P=0.003)。(2)光合参数表现为光饱和点处的净光合速率(P_(n))、气孔导度(G_(s))、叶片羧化速率(CE)、光饱和点(LSP)、最大净光合速率(P_(max))、光补偿点(LCP)、蒸腾速率(T_(r))、气孔限制值(L_(s))、暗呼吸速率(R_(d))这9个光合参数的均值乔木树种高于灌木树种(P0.05)。(3)乔灌木树种分解系数(k)与P_(n)、LSP、P_(max)、G_(s)、CE、LCP呈显著负相关关系,与R_(d)无明显相关性;P_(n)和P_(max)存在多重共线性,逐步回归结果表明P_(n)对k的解释和指示作用最强。【结论】光照强度通过影响叶片形态以及养分含量进而影响凋落叶的分解速率,使得乔木树种虽然有更高的光合参数,但分解系数比灌木树种更低,即分解速率更慢,存在光照强度—叶片形态、养分含量—凋落叶分解速率的连通关系;P_(n)、G_(s)、CE、LSP、P_(max)、LCP基本符合叶经济学谱理论,P_(n)可以解释和预测叶凋落物的分解速率。

关键词： Olson模型分解系数光响应曲线叶经济学谱

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结构水平-扭转耦合振动控制研究

工业建筑 2005年第Z1期35卷 423-426页

作者：潘颖刘立厚盛严上海工程技术大学基础学院上海200336 烟台大学土木工程学院烟台264005

运用调谐质量阻尼器(TMD)对结构水平-扭转振动进行控制。建立了扭转耦合结构控制的三维有限元模型;为了提高TMD的有效性,使模态位移响应的均方值之比(结构有无TMD)最小化,对TMD参数进行优化。数值算例表明本文方法对长宽比较大的结构切... 详细信息

运用调谐质量阻尼器(TMD)对结构水平-扭转振动进行控制。建立了扭转耦合结构控制的三维有限元模型;为了提高TMD的有效性,使模态位移响应的均方值之比(结构有无TMD)最小化,对TMD参数进行优化。数值算例表明本文方法对长宽比较大的结构切实有效。

关键词：水平-扭转振动 TMD 地震响应控制