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Zinc-assisted synthesis of imidazolium-tetrazolate bi-heterocyclic zwitterions with variable alkyl bridge length

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Science China Chemistry 2012年第8期55卷 1620-1626页

作者： DRAB David M. SHAMSHINA Julia L. SMIGLAK Marcin COJOCARU O. Andreea KELLEY steven p. ROGERS Robin D. Center for Green Manufacturing and Department of Chemistry The University of Alabama Tuscaloosa AL 35487 USA

Zinc halide-complexed alkyl-bridged bi-heterocycles were obtained as zwitterions from the Click reaction of a series of N-cyanoalkyl-N-alkylimidazolium halide ionic liquids with sodium azide. Reaction optimization sho... 详细信息

关键词： Click chemistry ionic liquids heterocycle coordination chemistry

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Relational and Euclidean Temporal Space

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Journal of Applied Mathematics and physics 2024年第2期12卷 683-719页

作者： steven D. p. Moore Independent Researcher Milton Canada

In mathematics, space encompasses various structured sets such as Euclidean, metric, or vector space. This article introduces temporal space—a novel concept independent of traditional spatial dimensions and frames of reference, accommodating multiple object-oriented durations in a dynamical system. The novelty of building temporal space using finite geometry is rooted in recent advancements in the theory of relationalism which utilizes Euclidean geometry, set theory, dimensional analysis, and a causal signal system. Multiple independent and co-existing cyclic durations are measurable as a network of finite one-dimensional timelines. The work aligns with Leibniz’s comments on relational measures of duration with the addition of using discrete cyclic relational events that define these finite temporal spaces, applicable to quantum and classical physics. Ancient formulas have symmetry along with divisional and subdivisional orders of operations that create discrete and ordered temporal geometric elements. Elements have cyclically conserved symmetry but unique cyclic dimensional quantities applicable for anchoring temporal equivalence relations in linear time. We present both fixed equivalences and expanded periods of temporal space offering a non-Greek calendar methodology consistent with ancient global timekeeping descriptions. Novel applications of Euclid’s division algorithm and Cantor’s pairing function introduce a novel paired function equation. The mathematical description of finite temporal space within relationalism theory offers an alternative discrete geometric methodology for examining ancient timekeeping with new hypotheses for Egyptian calendars.

关键词： Relationalism pairing Function Equation Discrete Euclidean Timelines Ancient Timekeeping

Advancements in Time Modeling: Relationalism, Divisional Structures, and Geometry

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Journal of Applied Mathematics and physics 2024年第10期12卷 3358-3383页

作者： steven D. p. Moore Independent Researcher Milton Canada

This article broadens terminology and approaches that continue to advance time modelling within a relationalist framework. Time is modeled as a single dimension, flowing continuously through independent privileged points. Introduced as absolute point-time, abstract continuous time is a backdrop for concrete relational-based time that is finite and discrete, bound to the limits of a real-world system. We discuss how discrete signals at a point are used to temporally anchor zero-temporal points [t = 0] in linear time. Object-oriented temporal line elements, flanked by temporal point elements, have a proportional geometric identity quantifiable by a standard unit system and can be mapped on a natural number line. Durations, line elements, are divisible into ordered unit ratio elements using ancient timekeeping formulas. The divisional structure provides temporal classes for rotational (Rt24t) and orbital (Rt18) sample periods, as well as a more general temporal class (Rt12) applicable to either sample or frame periods. We introduce notation for additive cyclic counts of sample periods, including divisional units, for calendar-like formatting. For system modeling, unit structures with dihedral symmetry, group order, and numerical order are shown to be applicable to Euclidean modelling. We introduce new functions for bijective and non-bijective mapping, modular arithmetic for cyclic-based time counts, and a novel formula relating to a subgroup of pythagorean triples, preserving dihedral n-polygon symmetries. This article presents a new approach to model time in a relationalistic framework.

关键词： Relationalism Mohist Geometry Euclidean Geometry Relational-Time Discrete-Time Continuous-Time planck Time Zero-Time

Separating Space and Time for Dimensional Analysis and Euclidean Relational Modeling

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Journal of Applied Mathematics and physics 2023年第9期11卷 2704-2738页

作者： steven D. p. Moore Independent Researcher Milton Canada

The theory of relativity links space and time to account for observed events in four-dimensional space. In this article we describe an alternative static state causal discrete time modeling system using an omniscient viewpoint of dynamical systems that can express object relations in the moment(s) they are observed. To do this, three key components are required, including the introduction of independent object-relative dimensional metrics, a zero-dimensional frame of reference, and application of Euclidean geometry for modeling. procedures separate planes of matter, extensions of space (relational distance) and time (duration) using object-oriented dimensional quantities. Quantities are converted into base units using symmetry for space (Dihedral360), time (Dihedral12), rotation (Dihedral24), and scale (Dihedral10). Geometric elements construct static state outputs in discrete time models rather than continuous time using calculus, thereby using dimensional and positional natural number numerals that can visually encode complex data instead of using abstraction and irrationals. Static state Euclidean geometric models of object relations are both measured and expressed in the state they are observed in zero-time as defined by a signal. The frame can include multiple observer frames of reference where each origin, point, is the location of a distinct privileged point of reference. Two broad and diverse applications are presented: a one-dimensional spatiotemporal orbital model, and a thought experiment related to a physical theory beyond planck limits. We suggest that expanding methodologies and continued formalization, novel tools for physics can be considered along with applications for computational discrete geometric modeling.

关键词： Spacetime Relationalism Quantum Classical Signal Discrete Geometry

The characteristics, origins, and geodynamic settings of supergiant gold metallogenic provinces

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Science China Earth Sciences 2000年第S1期43卷 1-68页

作者： Robert Kerrich Richard Goldfarb David Groves steven Garwin Department of Geological Sciences University of Saskatchewan Saskatoon SK S7N 5E2 Canada United States Geological Survey Box 25046 MS 964 Denver Federal Center Denver CO 80225-0046 USA Centre for Strategic Mineral Resources Department of Geology and Geophysics University of Western Australia Nedlands 6907 Western Australia Newmont Mining Corporation 1700 Lincoln Street Denver Colorado 80203 USA Correspondence should be addressed to Kerrich

There are six distinct classes of gold deposits, each represented by metallogenic provinces, having 100's to > 1 000 tonne gold production. The deposit classes are: (1) erogenic gold; (2) Carlin and Carlin-like gold deposits; (3) epithermal gold-silver deposits; (4) copper-gold porphyry deposits; (5) iron-oxide copper-gold deposits; and (6) gold-rich volcanic hosted massive sul-fide (VMS) to sedimentary exhalative (SEDEX) deposits. This classification is based on ore and alteration mineral assemblages; ore and alteration metal budgets; ore fluid pressure(s) and compositions; crustal depth or depth ranges of formation; relationship to structures and/or magmatic intrusions at a variety of scales; and relationship to the p-T-t evolution of the host terrane. These classes reflect distinct geodynamic settings. Orogenic gold deposits are generated at mid-crustal (4-16 km) levels proximal to terrane boundaries, in transpressional subduction-accretion complexes of Cordilleran style erogenic belts; other orogenic gold provinces form inboard by delamina-tion of mantle lithosphere, or plume impingement. Carlin and Carlin-like gold deposits develop at shallow crustal levels (provinces may involve asthenosphere plume impingement on the base of the lithosphere. Epithermal gold and copper-gold porphyry deposits are sited at shallow crustal levels in continental margin or intraoceanic arcs. Iron oxide copper-gold deposits form at mid to shallow crustal levels; they are associated with extensional intracratonic anorogenic magmatism. proterozoic examples are sited at the transition from thick refractory Archean mantle lithosphere to thinner proterozoic mantle lithosphere. Gold-rich VMS deposits are hydrothermal accumulations on or near the sea-floor in continental or intraoceanic back arcs.The compressional tectonics of orogenic gold deposits is generated by terrane accretion; high heat flow stems

关键词： gold deposit orogenic gold deposit geodynamics tectonic setting supercontinent.

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First demonstration of an all-solid-state optical cryocooler

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Light(Science & Applications) 2018年第1期7卷 922-931页

作者： Markus p.Hehlen Junwei Meng Alexander R.Albrecht Eric R.Lee Aram Gragossian steven p.Love Christopher E.Hamilton Richard I.Epstein Mansoor Sheik-Bahae Los Alamos National Laboratory P.O.Box 1663Los AlamosNM 87545USA Department of physics&Astronomy University of New MexicoAlbuquerqueNM 87131USA

Solid-state optical refrigeration uses anti-Stokes fluorescence to cool macroscopic objects to cryogenic temperatures without *** such as Yb3+-doped YLiF4(YLF:Yb)have previously been laser-cooled to 91 *** this study,we show for the first time laser cooling of a payload connected to a cooling crystal.A YLF:Yb crystal was placed inside a Herriott cell and pumped with a 1020-nm laser(47 W)to cool a HgCdTe sensor that is part of a working Fourier Transform Infrared(FTIR)spectrometer to 135 *** first demonstration of an all-solid-state optical cryocooler was enabled by careful control of the various desired and undesired heat *** heating of the payload was minimized by using a single-kink YLF thermal link between the YLF:Yb cooling crystal and the copper coldfinger that held the HgCdTe *** adhesive-free bond between YLF and YLF:Yb showed excellent thermal *** laser-cooled assembly was then supported by silica aerogel cylinders inside a vacuum clamshell to minimize undesired conductive and radiative heat loads from the warm *** structure can serve as a baseline for future optical cryocooler devices.

关键词： optical pumped desired

The effect of biochar on mycorrhizal fungi mediated nutrient uptake by coconut(Cocos nucifera L.)seedlings grown on a Sandy Regosol

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Biochar 2022年第1期4卷 56-73页

作者： Gertrude Scynthya Nirukshan Sanathanie Ranasinghe steven Sleutel Department of Environment Ghent UniversityCoupure Links 6539000 GhentBelgium. Coconut Research Institute Lunuwila 61150Sri Lanka

Biochar amendment of soil may ameliorate inherently infertile soils,such as in the typical coconut(Cocos nucifera L.)growth areas along tropical coasts,where,moreover,temporary moisture stress commonly *** conducted a pot experiment to evaluate the effects of biochar soil amendment(1%w/w)produced from Gliricidia sepium stems(BC-Gly)and rice husks(BC-RiH)on the growth of coconut seedlings and on N and p uptake mediated by mycorrhizae under wet or dry conditions in a Sandy *** pots were divided into root and hyphal zones by a nylon mesh,where 15N labelled N and p nutrients were only provided in the hyphal *** wet conditions,biochar applica-tion did not affect plant growth,while under dry conditions,the BC-Gly increased root and plant growth similar to that under wet ***-Gly increased the acidic pH of the soil to a neutral level,and the microbial community shifted towards a higher fungal *** p accumulated(pacc)in roots was higher with BC-Gly and BC-RiH under dry and wet conditions,*** weakly correlated with the abundance of arbuscular mycorrhizal fungi(AMF)in the hyphal *** BC-Gly roots showed lower N derived from *** conclude that biochar application has no impact on crop growth under wet conditions,while under dry conditions,BC-Gly stimulates crop growth and p uptake,probably through liming induced p availability but also possibly by some enhancement of AMF *** shift in the fungal-oriented microbial community and reduced plant fertilizer N uptake suggested that BC-Gly acted as an additional N source.

关键词： Coconut growing soil 15N isotope labelling Root-exclusion study container phosphorus Moisture stress

MgCl2和Gpp（NH）p对腺苷A1受体激动剂和拮抗剂结合的作用比较（英文）

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Acta pharmacologica Sinica 2003年第8期24卷 3-14+110页

作者： Keith FINLAYSON,MAEMOTO Takuya,steven p BUTCHER,John SHARKEY,Henry J OLVERMAN Fujisawa Institute of Neuroscience Fujisawa Institute of Neuroscience Fujisawa Institute of Neuroscience Division of Neuroscience University of Edinburgh Level 6 Appleton Tower Crichton Street. Edinburgh EH8 9LE UK Division of Neuroscience University of Edinburgh Level 6 Appleton Tower Crichton Street. Edinburgh EH8 9LE UK

AIM: To investigate modulation of antagonist and agonist binding to adenosine A1receptors by MgCl2and 5'-guanylimidodiphosphate (Gpp（NH）p) using rat brain membranes and the A1antagonist [3H]-8-cyclopentyl-1,3-dipropylxanthine （[3H]DpCpX） and the A1agonist [3H]-2-chloro-N6-cyclopentyladenosine （[3H]CCpA）. METHODS: parallel saturation and inhibition studies were performed using well-characterised radioligand binding assays and a Brandel Cell Harvester. RESULTS: MgCl2produced a concentration-dependent decrease （44%）, whereas Gpp（NH）p increased [3H]DpCpX binding （19%）. In [3H]DpCpX competition studies, agonist affinity was 1.5-14.6-fold higher and 4.6-10-fold lower in the presence of 10 mmol/L MgCl2and 10 μmol/L Gpp（NH）p respectively; antagonist affinity was unaffected. The decrease in agonist affinity with increasing Gpp（NH）p concentrations was due to a reduction in the proportion of binding to the high affinity receptor state. In contrast to [3H]DpCpX, MgCl2produced a concentration-

关键词：嘌呤p1受体放射配位体测定氯化镁鸟苷酰亚氨二磷酸脑

Observer-based fault detection scheme for a class of discrete time-delay systems

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Journal of Systems Engineering and Electronics 2004年第3期15卷 288-294页

作者：钟麦英张承慧 Ding steven X Lain James ControlScienceandEngineeringSchool ShandongUniversityJinan250061P.R.China Gerhard-Mercator-UniversityDuisburg Germany DepartmentofMechanicalEngineering TheUniversityofHongKongP.R.China

In this contribution, robust fault detection problems for discrete time-delay systems with l2-norm bounded unknown inputs are studied. The basic idea of our study is first to introduce a state-memoryless observer-based fault detection filter (FDF) as the residual generator and then to formulate such a FDF design problem as an Hen optimization problem in the sense of increasing the sensitivity of residual to the faults, while simultaneously enhancing the robustness of residual to unknown input as well as plant input. The main results consist of the formulation of such a residual generation optimization problem, solvability conditions and the derivation of an analytic solution. The residual evaluation problem is also considered, which includes the determination of residual evaluation function and threshold. A numerical example is used to demonstrate the proposed fault detection scheme.

关键词： residual generator robustness unknown input time-delay system post-filter.

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