69,342 research outputs found
Al-H-C chemistry
No full textThe synthesis of LAI(OH)(2), LAI(SH)(2), LAI(SeH)(2), and LAI(NH2)(2) (L = HC(CMeNAr)(2), Ar = 2,6-iPr(2)C(6)H(3)) is described. For the preparation of LAI(SH)(2) from LAIH(2) in the presence of sulfur a catalyst is required, whereas LAI(OH)(2) and LAI(NH2)(2) are obtained in the presence of a N-heterocyclic carbene as a HCl acceptor. The starting material for the latter reaction is LAICl(2). The organometallic hydroxides are environmentally friendly, in comparison to the metal halides, due to their OH functionality resembling that of water. The compounds are interesting precursor for the preparation of heterobimetallic compounds e.g. LAI(mu-S)(2)ZrCP2
Unusual anions [LAI(SH)(S)](-) and [LAI(S)(2)](2-) stabilized by weakly coordinating imidazoliurn cations. Synthesis of LAI(SSiMe2)(2)O (L HC[C(Me)N(Ar)](2), Ar=2,6-iPr(2)C(6)H(3))
No full textDeprotonation of an Al-SH moiety has been achieved easily by using N-heterocyclic carbene as the base. Monomeric mono- and bis-imidazolium salts [CtH+][LAI(SH)(S)](-) ([CtH+] = N,N'-bis-tert-butylimidazolium), [CmH+][LAI(SH)(S)](-), and [CmH+](2)[LAI(S)(2)](2) ([CmH+] = N,N'-bismesitylimidazolium), containing unusual anions [LAI(SH)(S)](-) and [LAI(S)(2)](2-), have been synthesized in nearly quantitative yields, Furthermore, [CmH+](2)[LAI(S)(2)](2) has been successfully used for the preparation of LAI(SSiMe2)(2)O containing the [O(Me2SiS)(2)](2-) ligand
Impact of sea-breeze air masses laden with ozone on inland surface ozone concentration, a case study of the northern coast of Taiwan
No full textExperimental investigation of ozone accumulation overnight during a wintertime ozone episode in south Taiwan
No full textLetter from C. H. Gensler, Havasupai Agency to Carl Hayden
No full textLetter from C. H. Gensler expressing concern on behalf of the Havasupai Tribe regarding the proposed park boundaries
Citations of the author H C Rajpoot
No full textThe list of the articles, research papers, theses, and book chapters globally citing the author H. C. Rajpoot</p
Optical instruments for measuring leaf area index in low vegetation : application in Arctic ecosystems
Full text linkAuthor Posting. © Ecological Society of America, 2005. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 15 (2005): 1462–1470, doi:10.1890/03-5354.Leaf area index (LAI) is a powerful diagnostic of plant productivity. Despite the fact that many methods have been developed to quantify LAI, both directly and indirectly, leaf area index remains difficult to quantify accurately, owing to large spatial and temporal variability. The gap-fraction technique is widely used to estimate the LAI indirectly. However, for low-stature vegetation, the gap-fraction sensor either cannot get totally underneath the plant canopy, thereby missing part of the leaf area present, or is too close to the individual leaves of the canopy, which leads to a large distortion of the LAI estimate. We set out to develop a methodology for easy and accurate nondestructive assessment of the variability of LAI in low-stature vegetation. We developed and tested the methodology in an arctic landscape close to Abisko, Sweden.
The LAI of arctic vegetation could be estimated accurately and rapidly by combining field measurements of canopy reflectance (NDVI) and light penetration through the canopy (gap-fraction analysis using a LI-COR LAI-2000). By combining the two methodologies, the limitations of each could be circumvented, and a significantly increased accuracy of the LAI estimates was obtained. The combination of an NDVI sensor for sparser vegetation and a LAI-2000 for denser vegetation could explain 81% of the variance of LAI measured by destructive harvest. We used the method to quantify the spatial variability and the associated uncertainty of leaf area index in a small catchment area.This research was funded by U.S. National Science Foundation
grant DEB0087046
Letter from Carl Hayden to C. H. Gensler
No full textLetter from Carl Hayden to C. H. Gensler informing him of the proposed Grand Canyon National Park bill
Letter from C. H. Gensler, Havasupai Agency to Carl Hayden
No full textLetter from C. H. Gensler to Carl Hayden asking for a meeting in regards to the Havasupai pasture land in light of the national park bill
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