检索结果-南通市图书馆

Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

引用

Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Champika Bandara Tithira Lakkana Shanika Jayasinghe david Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi I.A.U.N.Gunatilleke C.V.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

双螺杆膨化机与水产饲料加工

引用

中国粮油学报 2006年第3期21卷 426-433页

作者：石戴卫美国金地集团北京101119

膨化加工技术具有其他饲料加工技术无可比拟的优越性,膨化水产饲料是一种低污染、低浪费、高效率的优质环保型饲料。挤压膨化加工技术具有独特的优点:原料使用范围广、淀粉的糊化程度高、水中稳定性远远高于普通颗粒饲料,且由于挤压颗... 详细信息

膨化加工技术具有其他饲料加工技术无可比拟的优越性,膨化水产饲料是一种低污染、低浪费、高效率的优质环保型饲料。挤压膨化加工技术具有独特的优点:原料使用范围广、淀粉的糊化程度高、水中稳定性远远高于普通颗粒饲料,且由于挤压颗粒的结构比较疏松(密度可调),有利于采用后喷涂技术,避免热敏性原料的损失,提高营养价值,降低生产成本。挤压膨化技术在水产饲料的应用发展十分迅猛,水产膨化饲料在水产养殖中的应用也日趋广泛和成熟。要想生产出熟化均匀、外观熟化度高且在水中可沉可浮的饲料,只有采用双螺杆膨化机。以金地三福为代表的国内优秀膨化机生产厂家不断研究,致力于提高膨化机的各项性能及实现全自动控制,从而推动我国水产养殖业的发展。

关键词：双双螺杆膨化机水产饲料加工

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Business statistics [5th ed.]

引用

丛书名：外国优秀统计学教材系列丛书·影印版

2003年

作者： david F. Groebner ... [等]

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Transporting Mammalian Cells at Ambient Temperature:A Viable Alternative to Dry Ice

引用

Advances in Bioscience and Biotechnology 2017年第4期8卷 127-133页

作者： Steingrimur Stefansson Seunghyun Han Ye In Jeon david S.Chung Peter Hwang Huyen Le John L.Warden david Ho HeMemics Biotechnologies Inc RockvilleUSA Johns Hopkins University BaltimoreUSA George Washington University WashingtonDCUSA Division of Biology and Medicine Brown UniversityProvidenceUSA Thomas Jefferson High School for Science and Technology AlexandriaUSA Nauah Solutions McleanUSA

The most common method of shipping cells between institutes and companies is sending them frozen, usually treated with anti-freeze solution (most commonly DMSO because it is less toxic than many alternatives), and then packaging them in dry ice for shipment. However many countries place restrictions on dry ice shipments. An alternative to shipping frozen cell vials is to send flasks of growing cells in media. This also has problems because cells in media have limited viability and the flasks can leak. Here we report on an alternative method for shipping viable cells at ambient temperature without dry ice or in media filled flasks. In this study we report on the development and properties of HemSol?. This is an inexpensive, eco-friendly and protects cell integrity at ambient temperature while maintaining viability. We have previously shown that HemSol? protects platelet and RBC function in cold storage and circulating tumor cells up to 6 days. Therefore we wanted to know if HemSol? could also be used to transport live cells. Since HemSol? is a liquid, we experimented with encasing the cells with HemSol? and gelatin so as to prevent dry ice shipment of cells and circumvent the shipping of cells in media. We performed mock shipping experiments where cells were stored in HemSol? gel kept at room temperature on a lab benchtop and cells stored in dry ice was also kept on lab benchtop for up to 2 days. After the mock shipping period, we analyzed cells for their functions. Our results show that cells in HemSol? gel have greater than 95% viability and restored biological functions in 2 hours, whereas, cells shipped in dry ice required more than 24 hours to recover and needed media change to remove the DMSO.

关键词： HemSol^(TM) HemSol^(TM) Gel Transportation Short Term Storage Cells Shipment Dry Ice Ambient Temperature Shipment

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

北美推展中国文化的接受群体分析

引用

社会科学 2012年第2期 65-76页

作者：吴琦幸美国圣塔莫妮卡学院现代语言文化系

中国文化在美国推广和展现有七次震撼性的巡回,在美国主流接受群体中获得了极大的反响。1849年华工赴美淘金,中国文化以群像出现在美洲大陆。此后李鸿章访问纽约、梅兰芳访美演出、宋美龄国会演讲、邓小平中美建交之后的亮相、中国经济... 详细信息

中国文化在美国推广和展现有七次震撼性的巡回,在美国主流接受群体中获得了极大的反响。1849年华工赴美淘金,中国文化以群像出现在美洲大陆。此后李鸿章访问纽约、梅兰芳访美演出、宋美龄国会演讲、邓小平中美建交之后的亮相、中国经济地位提升华人新移民以群体形象融入主流、白先勇策划组织《牡丹亭》加州巡演,美国的主流接受群体以一种个人魅力、皇家文化、通俗文化的共鸣来欢迎中国元素。环视近年来的中国文化在美国的推展,效果似乎不够显著,其原因在于忽视了推展中国文化的接受群体研究和操作过程。

关键词：中国文化美国主流华工淘金李鸿章访美邓小平梅兰芳个人魅力

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

西方文化研究的演变对我国体育文化研究的启示

引用

上海体育学院学报 2014年第1期38卷 47-51页

作者：马德浩季浏 david L. Andrews 华东师范大学体育与健康学院上海200241 马里兰大学运动系美国20742

在国家提出文化大发展的战略规划后,复兴体育文化研究的呼声日趋高涨。复兴的前提是找到合适的切入点和研究范式,并结合中国国情进行创造性的解读与建构。基于此,对西方文化研究的发展历程进行谱系性追溯,并对其研究特点及未来走向进行... 详细信息

在国家提出文化大发展的战略规划后,复兴体育文化研究的呼声日趋高涨。复兴的前提是找到合适的切入点和研究范式,并结合中国国情进行创造性的解读与建构。基于此,对西方文化研究的发展历程进行谱系性追溯,并对其研究特点及未来走向进行展望。认为:我国体育文化研究在理论借鉴上应做到"西体中用";在视域选择上应倡导多元化;在方法选择上应强调多样性;在思路把握上应注重交互性。

关键词：西方文化研究中国体育文化演变

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Alternatives to surgery in children with mild OSA

引用

World Journal of Otorhinolaryngology-Head and Neck Surgery 2021年第3期7卷 228-235页

作者： david Gozal Mahmoud Ismail Pablo E.Brockmann Department of Child Health and Child Health Research Institute and MU Women and Children’s HospitalUniversity of Missouri School of MedicineColumbiaMOUSA Department of Neurology and Sleep Medicine University of Missouri School of MedicineColumbiaMOUSA Department of Pediatric Cardiology and Pulmonology Division of PediatricsSchool of MedicinePontificia Universidad Católica de ChileSantiagoChile Pediatric Sleep Center School of MedicinePontificia Universidad Católica de ChileSantiagoChile

Precision medicine requires coordinated and integrated evidence-based combinatorial approaches so that diagnosis and treatment can be tailored to the individual *** this context,the treatment approach to mild obstructive sleep apnea(OSA)is fraught with substantial debate as to what is mild OSA,and as to what constitutes appropriate *** such,it is necessary to first establish a proposed consensus of what criteria need to be employed to reach the diagnosis of mild OSA,and then examine the circumstances under which treatment is indicated,and if so,whether and when anti-inflammatory therapy(AIT),rapid maxillary expansion(RME),and/or myofunctional therapy(MFT)may be indicated.

关键词： Obstructive sleep apnea Children Antiinflammatory Myofunctional therapy Rapid maxillary expansion Adenotonsillectomy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Large-scale permafrost degradation as a primary factor in Larix sibirica forest dieback in the Khentii massif,northern Mongolia

引用

Journal of Forestry Research 2020年第1期31卷 197-208页

作者： david Juricka Jitka Novotna Jakub Houska Jana Parilkova Jan Hladky Vaclav Pecina Hana Cihlarova Marcela Burnog Jakub Elbl Zdena Rosicka Martin Brtnicky Jindrich Kynicky Department of Geology and Pedology Faculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 161300 BrnoCzech Republic Central European Institute of Technology Brno University of TechnologyPurkynova 656/12361200 BrnoCzech Republic Institute of Water Structures Faculty of Civil EngineeringBrno University of TechnologyZizkova 1760200 BrnoCzech Republic

The objective of this study is to investigate the potential causes of widespread Larix sibirica *** observed in the Khentii massif of northern *** ratio of deadwood to living trees in affected stands in the Goricho region,the southernmost study site situated close to the Gobi Desert,was as high as 3.6:*** fluctuations monitored over 2 years using electrical impedance spectrometry revealed that the Goricho study site had higher soil moisture levels than the two less affected sites Barun Bayan and Dzun *** soil moisture was recorded in an area characterized by highly skeletal soils,ones with more than 35%by volume of rock fragments,and comparatively shallow soil horizons,from valley to *** layer of permafrost influencing hydrogeological processes is much deeper in the Goricho region compared to the undisturbed study *** analysis confirmed a significant number of dead *** on sites with developed *** forest stands,however damaged,grow in this region on well-drained scree slopes or on rocky *** mass mortality observed for *** may be directly linked to accelerated permafrost thaw in the area bordered by the Tuul and the Terelj *** assumption is that *** root system necrosis occurred as a result of long-term waterlogging of developed soils with high spatial heterogeneity,normally able to absorb high quantities of *** areas unaffected were scree fields and rocky bastions characterized by adequate *** of our findings support the primary stages of large-scale permafrost thaw,i.e.,correlating increases in soil moisture with increasing permafrost active layer thickness.

关键词： Larix sibirica Mortality Permafrost thawing Waterlogging Mongolia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

捻军:历史人类学可以问什么问题?

引用

清史研究 2023年第6期140卷 12-23页

作者：科大卫香港中文大学历史系中国香港

捻军的历史是清史研究范围内一个长期被关注的问题,也是一个多年来历史学者配合田野考察与文献考据作为研究方法的问题。本文从20世纪50年代以江地与马昌华先生为首的田野考察与文献研究出发,提出近年来历史人类学从“礼仪标签”的概念... 详细信息

捻军的历史是清史研究范围内一个长期被关注的问题,也是一个多年来历史学者配合田野考察与文献考据作为研究方法的问题。本文从20世纪50年代以江地与马昌华先生为首的田野考察与文献研究出发,提出近年来历史人类学从“礼仪标签”的概念所能引申的问题。本文考虑把“捻”或“捻子”作为一个行为的标签,放到法律文书,对“捻”在文献出现的频繁有没有影响。再者,所谓“结捻”的群众,为什么会在太平军北伐的时候竖旗起义。

关键词：捻盐枭礼仪标签掠夺性策略

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Observation of coupling between zero- and two- dimensional semiconductor systems based on anomalous diamagnetic effects

引用

Nano Research 2016年第2期9卷 306-316页

作者： Shuo Cao Jing Tang Yue Sun Kai Peng Yunan Gao Yanhui Zhao Chenjiang Qian Sibai Sun Hassan Ali Yuting Shao Shiyao Wu Feilong Song david A. Williams Weidong Sheng Kuijuan Jin Xiulai Xu Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Hitachi Cambridge Laboratory Cavendish Laboratory Cambridge CB3 OHE UK Department of Physics Fudan University Shanghai 200433 China Collaborative Innovation Center of Quantum Matter Beijing 100084 China

We report the direct observation of coupling between a single self-assembled InAs quantum dot and a wetting layer, based on strong diamagnetic shifts of many-body exciton states using magneto-photoluminescence spectroscopy. An extremely large positive diamagnetic coefficient is observed when an electron in the wetting layer combines with a hole in the quantum dot; the coefficient is nearly one order of magnitude larger than that of the exciton states confined in the quantum dots. Recombination of electrons with holes in a quantum dot of the coupled system leads to an unusual negative diamagnetic effect, which is five times stronger than that in a pure quantum dot system. This effect can be attributed to the expansion of the wavefunction of remaining electrons in the wetting layer or the spread of electrons in the excited states of the quantum dot to the wetting layer after recombination. In this case, the wavefunction extent of the final states in the quantum dot plane is much larger than that of the initial states because of the absence of holes in the quantum dot to attract electrons. The properties of emitted photons that depend on the large electron wavefunction extents in the wetting layer indicate that the coupling occurs between systems of different dimensionality, which is also verified from the results obtained by applying a magnetic field in different configurations. This study paves a new way to observe hybrid states with zero- and two-dimensional structures, which could be useful for investigating the Kondo physics and implementing spin-based solid-state quantum information processing.

关键词： magneto-photoluminescence InAs quantum dots wetting layer strong diamagnetic effects

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：