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Synthesis and properties of novel nitro-based thermally stable energetic compounds

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Defence Technology（防务技术） 2021年第3期17卷 775-784页

作者： Łukasz Gutowski Stanisław Cudziło Military University of Technology Faculty of Advanced Technologies and ChemistryGen.Sylwestra Kaliskiego 2 Street00-908WarsawPoland

This paper reviews the achievements in the field of synthesis of new thermally resistant explosive compounds in the years 2009 through 2019. The performance characteristics of these compounds(sensitivity, thermal decomposition parameters, and detonation parameters) were compared with those of 1,3,5-triamino-2,4,6-trinitrobenzene, which still seems to be an unrivalled model of a thermally resistant and generally low-sensitivity explosive material. New thermally stable explosives(TSEs) were found among macromolecular compounds with tri-and dinitrophenyl groups, nitro and amine-nitro derivatives of azoles, and polynitro derivatives of calixarenes. Some of them match TATB in terms of thermal resistance and additionally have higher detonation parameters.

关键词： Heat resistant explosives Detonation parameters Synthesis Nitration

Interactive influence of rainfall manipulation and livestock grazing on species diversity of the herbaceous layer community in a humid savannah in Kenya

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Plant Diversity 2019年第3期41卷 198-205页

作者： Joseph o.ondier Daniel o.okach John C.onyango Dennis o.otieno Department of Botany Maseno University Private Bag Maseno Kenya Department of Biological Sciences Jaramogi Oginga Odinga University of Science and Technology P.O Box 210-40601 Bondo Kenya Department of Plant Ecology University of Bayreuth D-95440 Bayreuth Germany

Changes in rainfall regime and grazing pressure affect vegetation composition and diversity with ecological implications for savannahs. The savannah in East Africa has experienced increased livestock grazing and rainfall variability but the impacts associated with those changes on the herbaceous layer have rarely been documented. We investigated the effect of livestock grazing, rainfall manipulation and their interaction on the composition and diversity of the herbaceous community in the savannah for two years in Lambwe, Kenya. Rainfall manipulation plots were set up for vegetation sampling;these plots received either 50% more or 50% less rainfall than control plots. Simpson’s diversity and Bergere Parker indices were used to determine diversity changes and dominance respectively. The frequency of species was used to compute their abundance and their life forms as determined from the literature. Grazing significantly increased species diversity through suppression of dominant species. Rainfall manipulation had no significant impact on plant diversity in fenced plots, but rainfall reduction significantly reduced diversity in grazed plots. In contrast, rainfall manipulation had no impact on dominance in either fenced or grazed plots. The interaction of grazing and rainfall manipulation is complex and will require additional survey campaigns to create a complete picture of the implications for savannah structure and composition.

关键词： Plant diversity Grazing Rainfall Moist savannah

Predictors of new-onset atrial fibrillation in elderly patients with coronary artery disease after coronary artery bypass graft

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Journal of Geriatric Cardiology 2016年第5期13卷 444-449页

作者： Rubanenko o Anatol'evna Fatenkov o Veniaminovic Khokhlunov S Mikhaylovich Department of Faculty Therapy Samara State Medical Universtty Samara Russia Samara Regional Cardiology Centre Samara Russia

objective To identify the factors associated with the development of postoperative atrial fibrillation （PoAF） after coronary artery bypass graft （CABG） in elderly patients with coronary artery disease （CAD）. Methods A total of 81 patients with CAD who underwent CABG were enrolled in the study. Patients were divided into two groups： Group 1, without postoperative atrial fibrillation （59 patients, 74.6% men, mean age 65.8 ~ 4.0 years）; Group 2, with early new-onset atrial fibrillation after CABG （22 patients, 90.9% men, mean age 67.7 ＋ 5.4 years）. Interleukin （IL）-6, IL-8, IL-10, C-reactive protein （CRP）, fibrinogen, superoxide dismutase （SoD）, N-terminal pro-B-type natriuretic peptide （NT-proBNP）, and troponin I were studied. Results During the observation period, atrial fibrillation occurred in 27.2% cases, an average of 4.9 ±3.8 days after surgery. In group 2, the left atrium （LA） dimension was larger than in group 1 （43.9 ± 3.4 mm vs. 37.6 ±3.9 rnm, P 〈 0.001）. Patients with PoAF had significantly higher IL-6 （72.7 ±60.8 pg/mL vs. 38.0 ± 34.6 pg/mL, P = 0.04）, IL-8 （11.9 ± 6.0 pg/mL vs. 7.7± 5.4 pg/mL, P = 0.01） and SoD （2462.0 ± 2029.3 units/g vs. 1515.0 ± 1292.9 units/g, P = 0.04） compared with group without PoAF. The multivariate analysis showed that the odds ratio （oR） for PoAF development in patients with left atrium more than 39 mm was 2.1 [95% confidence interval （CI）： 1.2-3.8, P = 0.0004], IL-6 levels more than 65.18 pg/mL-1.4 （95% Ch 1.1-2.7, P = 0.009）, IL-8 levels more than 9.67 pg/mL-1.2 （95% CI： 1.1-3.7, P ： 0.009）, SoD more than 2948 units/g-1.1 （95% Ch 1.01-2.9, P = 0.04）. Conclusions In our study, the independent predictors of postoperative atrial fibrillation after CABG in elderly patients were left atrium dimension and the increased postoperative concentration of IL-6, IL-8 and superoxide dismutase.

关键词： Antioxidant Atrial fibrillation Coronary artery bypass graft Interleukins Troponin

Parallel loop recovery with quiescent compensation for high performance feedback control of systems with imperfect actuators

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Control Theory and Technology 2019年第3期17卷 201-215页

作者： Y.V.o'BRIEN J.F.o'BRIEN Department of Electrical and Computer Engineering University of Wyoming Laramie WY 82073 U.S.A.

Actuator limits and imperfections introduce multiple nonlinearities in a feedback *** standard mild-feedback systems (e.g.,PID) are intrinsically robust to such nonlinearities,the stability of large feedback systems is *** eliminates from consideration the usage of imperfect actuators in large feedback applications and available disturbance rejection as a result is not *** implementation of multiple-path nonlinear dynamic compensation (NDC),however,allows the combination of large feedback and imperfect actuation and is the focus of this *** nonlinearities due to actuator imperfection are often difficult to model,the stability of the NDC systems is assessed using multivariable absolute stability *** features of a parallel loop recovery system with loop transmission modulus reduction compensation in the quiescent condition are compared to an alternative approach of strict modulus reduction via nonlinear compensation for stability *** of the loop recovery approach is illustrated using experimental data from a voice-coil actuated disturbance rejection system.

关键词： Feedback control imperfect actuators nonlinear dynamic compensation

Vertical stratification of bat assemblages in flooded and unflooded Amazonian forests

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Current Zoology 2010年第4期56卷 469-478页

作者： Maria Joo Ramos PEREIRA Joo Tiago MARQUES Jorge M.PALMEIRIM Centro de Biologia Ambiental Departamento de Biologia Animal Faculdade de Ciências da Universidade de Lisboa Instituto de Desenvolvimento Sustentvel Mamirau

Tropical rainforests usually have multiple strata that results in a vertical stratification of ecological opportunities foranimals. We investigated if this stratification influences the way bats use the vertical space in flooded and unflooded forests of theCentral Amazon. Using mist-nets set in the canopy (17 to 35 m high) and in the understorey (0 to 3 m high) we sampled four sitesin upland unflooded forests (terra firme), three in forests seasonally flooded by nutrient-rich water (varzea), and three in forestsseasonally flooded by nutrient-poor water (igapo). Using rarefaction curves we found that species richness in the understorey andcanopy were very similar. An ordination analysis clearly separated the bat assemblages of the canopy from those of the understorey inboth flooded and unflooded habitats. Gleaning carnivores were clearly associated with the understorey, whereas frugivores wereabundant in both strata. of the frugivores, Carollinae and some Stenodermatinae were understorey specialists, but several Stenodermatinaemostly used the canopy. The first group mainly includes species that, in general, feed on fruits of understorey shrubs,whereas the second group feed on figs and other canopy fruits. We conclude that vertical stratification in bat communities occurseven within forests with lower canopy heights, such as Amazonian seasonally flooded forests, and that the vertical distribution ofbat species is closely related to their diet and foraging behaviour.

关键词： Amazon Bats Chiroptera Vertical stratification Floodplain

Gravitational form factors and nucleon spin structure

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Frontiers of physics 2016年第5期11卷 1-8页

作者： o.V. Teryaev Bogoliubov Laboratory of Theoretical Physics JINR 141980 Dubna Moscow Region Russia

Nucleon scattering by the classical gravitational field is described by the gravitational （energy- momentum tensor） form factors （GFFs）, which also control the partition of nucleon spin between the total angular momenta of quarks and gluons. The equivalence principle （EP） for spin dynamics results in the identically zero anomalous gravitomagnetic moment, which is the straightforward analog of its electromagnetic counterpart. The extended EP （ExEP） describes its （approximate） validity separately for quarks and gluons and, in turn, results in equal partition of the momentum and total angular momentum. It is violated in quantum electrodynamics and perturbative quantum chromodynamics （QCD）, but may be restored in nonperturbative QCD because of confinement and spontaneous chiral symmetry breaking, which is supported by models and lattice QCD calculations. It may, in principle, be checked by extracting the generalized parton distributions from hard exclu- sive processes. The EP for spin-1 hadrons is also manifested in inclusive processes （deep inelastic scattering and the Drell-Yan process） in sum rules for tensor structure functions and parton distributions. The ExEP may originate in either gravity-proof confinement or in the closeness of the GFF to its asymptotic values in relation to the mediocrity principle. The GFFs in time-like regions reveal some similarity between inflation and annihilation.

关键词： gravity form factors equivalence principle

Analysis of Sakiadis flow of nanofluids with viscous dissipation and Newtonian heating

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Applied Mathematics and Mechanics(English Edition) 2012年第12期33卷 1545-1554页

作者： o.D.MAKINDE Institute for Advance Research in Mathematical Modelling and Computations Cape Peninsula University of TechnologyP.O.Box 1906Bellville 7535South Africa

The combined effects of viscous dissipation and Newtonian heating on bound- ary layer flow over a moving flat plate are investigated for two types of water-based New- tonian nanofluids containing metallic or nonmetallic nanoparticles such as copper （Cu） and titania （Ti02）. The governing partial differential equations are transformed into ordinary differential equations through a similarity transformation and are solved numer- ically by a Runge-Kutta-Fehlberg method with a shooting technique. The conclusions are that the heat transfer rate at the moving plate surface increases with the increases in the nanoparticle volume fraction and the Newtonian heating, while it decreases with the increase in the Brinkmann number. Moreover, the heat transfer rate at the moving plate surface with Cu-water as the working nanofiuid is higher than that with Tio2-water.

关键词： Sakiadis flow nanofluid viscous dissipation Newtonian heating

Element diffusion ability in metasomatic agents and its effect on chemical characteristics of metasomatized peridotites

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Science China Earth Sciences 2006年第9期49卷 926-937页

作者： Y S o’Reilly GEMoC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney N.S.W. 2109 Australia

Detailed in situ LM-ICPMS researches on the composite xenoliths from Yingfengling volcano of Leizhou Peninsula, South China, indicate that most incompatible trace elements of clino- pyroxenes in composite xenoliths decrease spatially from pyroxenites to distal lherzolites, and com- patible elements and HREE increase steeply. The increasing and decreasing rate is distinct for dif- ferent trace elements, which give rise to element chromatographic fractionation within metasomatized lherzolites. The element chromatographic fractionation result actually from the difference in element diffusive rate in melts or fluids percolating through wall-rock lherzolites. Based on element variation profiles in composite xenoliths this study indicates that Sr, Nb, La and Ce have the highest diffusive mobility, MREE-HREE are moderate, and Zr, Hf, Ti, Ga and Sc are very low in most cases. Higher diffusive rates of LREE than HREE would enlarge the REE fractionation of metasomatized peridotites, and lower diffusive rate of Zr, Hf and Ti relative to neighbor REEs with similar incompatibility would cause the relative depletion of these elements in metasomatized peridotites. Trace elements com- monly have a higher diffusive rate in fluid-rich infiltrating melt, which will weaken element chroma- tographic fractionation during the metasomatism. The range of mantle metasomatism caused by sili- cate melt intrusion is very limited, generally within tens of centimeters wide. The width of metasoma- tized wall-rock peridotites near the pyroxenite or horblendite veins was strictly controlled by both melt volume and chemical characteristics.

关键词： composite xenolith, metasomatism, chromatographic fractionation, diffusive rate, Leizhou Peninsula.

Looking Back and Beyond Sendai:25 Years of International Policy Experience on Disaster Risk Reduction

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International Journal of Disaster Risk Science 2015年第1期6卷 1-7页

作者： Sálvano Briceo Science Committee Integrated Research on Disaster Risk(IRDR) Program of International Council for Science (ICSU)/International Social Science Council (ISSC)/United NationsInternational Strategy for Disaster Reduction (UNISDR)

The evolution in knowledge and application of disaster risk reduction in the 25 years of global cooperation on this issue has been uneven. While advances in knowledge have improved our understanding of the full nature of risk—the combination of hazards meeting vulnerability—the application of such knowledge has not been conducive to the development of institutional and technical mechanisms to address the full range of risk elements. Governance of risk(policies, legislation, and organizational arrangements) still focuses largely on preparing to respond to the hazards and planning for recovery. This leaves largely unattended the vulnerability component of risk, which is the only component on which change can be *** arrangements, risk assessments, early warning systems, and other institutional and technical capacities still concentrate on natural hazards and this is the main change that remains to be substantively addressed.

关键词： Climate change adaptation Disaster risk reduction Risk governance Risk management