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791.
The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is one of the most significant economic pests of citrus worldwide. This insect vectors three phloem-restricted bacteria in the genus Candidatus Liberibacter that cause huanglongbing (citrus greening), the most severe disease limiting citrus production worldwide. We examined the external morphology of the antennal sensilla of male and female D. citri using scanning electron microscopy (SEM) and determined the putative functions of the identified sensilla using transmission electron microscopic (TEM) techniques. The filiform antennae of D. citri were of the conventional type comprised of a basal scape, pedicel and a long, thread-like flagellum, which is composed of eight flagellomeres. Eleven morphologically unique sensillar types were found and described on the antennae of male and female D. citri. Of those identified, the two apical setae, multiporous types I and II sensilla trichoidea, and the antennal rhinaria were porous and may be involved in perception of host- and mate-related volatile chemicals. However, the aporous types I, II and III sensilla trichoidea may have mechanosensory functions and the chaetica sensilla, cavity sensilla and unidentified uniporous sensilla may be involved in proprioception, thermo-hygroreception and cold detection, respectively. The shape, external morphology and array of sensilla on the antennae of male and female D. citri were similar. The only major difference observed was in the morphology of the short apical setae, whose tips were recessed inward in females but not so in males. The results are discussed in relation to plausible roles of the identified sensilla in mate and host location by this species. 相似文献
792.
Outdoor spectral measurements in sub‐Sahara, South Africa in particular have not been documented probably due to lack of data or lack of proper methodologies for quantifying the spectral effects on photovoltaic performance parameters. Crystalline‐Si modules are widely used for system designs in most cases based on the data provided from indoor measurements or from maritime northern hemispheric conditions. As a result of this, PV systems fail to deliver their intended maximum power output. In this study, a methodology for quantifying outdoor spectral effects of c‐Si modules commonly found in the African continent is presented. The results of three crystalline‐Si modules indicate that these modules are affected as the spectrum shifts during seasons although these devices are perceived (without outdoor data) that their performance is not influenced by the seasonal changes in outdoor spectrum. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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795.
Alexander G. Sturm Tobias Santowski Julia I. Schweizer Dr. Lioba Meyer Dr. Kenrick M. Lewis Dr. Thorsten Felder Prof. Dr. Norbert Auner Prof. Dr. Max C. Holthausen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(36):8499-8502
The industrial production of monosilanes MenSiCl4−n (n=1–3) through the Müller–Rochow Direct Process generates disilanes MenSi2Cl6−n (n=2–6) as unwanted byproducts (“Direct Process Residue”, DPR) by the thousands of tons annually, large quantities of which are usually disposed of by incineration. Herein we report a surprisingly facile and highly effective protocol for conversion of the DPR: hydrogenation with complex metal hydrides followed by Si−Si bond cleavage with HCl/ether solutions gives (mostly bifunctional) monosilanes in excellent yields. Competing side reactions are efficiently suppressed by the appropriate choice of reaction conditions. 相似文献
796.
Theo Scholtes Stefan Woetzel Rob IJsselsteijn Volkmar Schultze Hans-Georg Meyer 《Applied physics. B, Lasers and optics》2014,117(1):211-218
The intrinsic relaxation rates of the vector magnetization of cesium vapor enclosed in microfabricated atomic magnetometer cells are investigated. Two methods—the optically detected magnetic resonance and the ground-state Hanle effect—are used to carry out automated measurements in dependence on cell temperature and nitrogen buffer gas pressure. The experimental results are compared with expected contributions of the different relaxation processes and in this way allow the discrimination between them to help further optimization of cell design. The methods are compared in terms of basic features, data quality, and practical applicability. 相似文献
797.
Dr. Bugga Balakrishna Arjun Menon Dr. Kecheng Cao Sebastian Gsänger Dr. Sebastian B. Beil Julia Villalva Oleksandr Shyshov Oliver Martin Prof. Dr. Andreas Hirsch Prof. Dr. Bernd Meyer Prof. Dr. Ute Kaiser Prof. Dr. Dirk M. Guldi Prof. Dr. Max von Delius 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18933-18945
798.
Glen B. Deacon Peter C. Junk Timothy J. Ness Regina Schwering Gerd Meyer 《Journal of chemical crystallography》2006,36(3):167-174
The X-ray crystal structures of (aqua)bis(cyclopentadienyl)chlorotitanium(IV) trifluoromethanesulfonate, bis(aqua)bis(cyclopentadienyl)titanium(IV) bis(trifluoromethanesul-fonate) and bis(cyclopentadienyl)bis(trifluoromethanesulfonato)titanium(IV) show a pseudo-tetrahedral array of Cp ring centroids and oxygen or oxygen and chloride donors around titanium, and varied long-range packing motifs dependent on the availability of hydrogen bond acceptors within the lattice. 相似文献
799.
Inside Cover: Synthesis of an All‐Ferric Cuboidal Iron–Sulfur Cluster [FeIII4S4(SAr)4] (Angew. Chem. Int. Ed. 36/2018)
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800.
Cong Tian Leonardo Massignan Tjark H. Meyer Prof. Dr. Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2018,57(9):2383-2387
Electrochemistry enabled C?H/N?H functionalizations at room temperature by external oxidant‐free cobalt catalysis. Thus, the sustainable cobalt electrocatalysis manifold proceeds with excellent levels of chemoselectivity and positional selectivity, and with ample scope, thus allowing electrochemical C?H activation under exceedingly mild reaction conditions at room temperature in water. 相似文献