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排序方式: 共有4755条查询结果,搜索用时 15 毫秒
1.
Journal of Optimization Theory and Applications - Pollution management models of Shallow Lake type identify a well-known class of infinite horizon optimal control problems, characterized by the... 相似文献
2.
3.
Numerical Algorithms - We introduce a modulus-based formulation for vertical linear complementarity problems (VLCPs) with an arbitrary number ? of matrices. This formulation can be used to... 相似文献
4.
Vito Gigante Laura Aliotta Maria Beatrice Coltelli Patrizia Cinelli Luigi Botta Francesco Paolo La Mantia Andrea Lazzeri 《Journal of polymer science. Part A, Polymer chemistry》2020,58(23):3264-3282
The development of biodegradable materials for tailored applications, particularly in the field of polymeric films and sheets, is a challenging technological goal as well as a contribution to help protect the environment. Poly(lactic) acid (PLA) is a promising substitute for several oil-based polymers; however, to overcome its thermal and mechanical drawbacks, researchers have developed solutions such as blending PLA with polybutylene adipate terephthalate (PBAT), which is capable of increasing the ductility of the final material. In this study, PLA/PBAT binary blends, with minimum possible content of nonrenewable materials, were examined from processing, thermal, morphological, and rheological perspective. An optimized PLA/PBAT ratio was chosen as the polymeric basis to obtain a biodegradable formulation by adding a biobased plasticizer and appropriate fillers to produce a micrometer film with tailored flexibility and tear resistance. The processing technology involved flat-die extrusion, followed by calendering. The tearing resistance of the produced film was investigated, and the results were compared with literature data. A study on the essential work of fracture was implemented to explore the mode III out-of-plane fracture resistance starting from a trouser tear test. 相似文献
5.
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Let P(G,λ) be the chromatic polynomial of a graph G with n vertices, independence number α and clique number ω. We show that for every λ≥n, ()α≤≤ ()
n
−ω. We characterize the graphs that yield the lower bound or the upper bound.?These results give new bounds on the mean colour
number μ(G) of G: n− (n−ω)()
n
−ω≤μ(G)≤n−α() α.
Received: December 12, 2000 / Accepted: October 18, 2001?Published online February 14, 2002 相似文献
7.
The concept of strong interactions need not be limited to the sector of physics taken by QCD. While this domain is investigated by RHIC, LHC will be able to probe potential new strong interactions simultaneously: Finding the precise mechanism for electroweak symmetry breaking is one of the prime problems of physics. Intricately linked to this point is the question after the true nature or even the existence of the Higgs boson. Here, we present stronly interacting theories providing an explanation for the hierarchy problem and leading to a light composite Higgs boson, favoured by experimental data. Our variation of the standard model is consistent with precision data. We achieve this accordance by using technifermions in a higher representation of their gauge group. Anomaly conditions require at least one extra lepton family for some of the theories whereby they contain a natural dark matter candidate. We can accurately determine the masses of said leptons from experimental data. 相似文献
8.
Ohne Zusammenfassung 相似文献
9.
Francesco Severi 《Annali di Matematica Pura ed Applicata》1940,19(1):153-242
Sunto. Costruzione dei fondamenti della geometria numerativa (computo della costanti, conservazione del numero, calcolo simbolico,
principio generalizzato diPlücker-Clebsch) dal punto di vista delle teorie (dovute all' Autore), che hanno fatto progredire e rinnovato tanta parte della moderna geometria
algebrica (teoria della base, varietà virtuali, sistemi d'equivalenza, teoria generale delle corrispondenze). Teorema d'esistenza
delle caratteristiche delle condizioni pure di data dimensione imposte agli elementi d'una varietà algebrica, anche in presenza
di elementi degeneri. Applicazioni (teoria delle caratteristiche inerenti a spazi lineari, risoluzione generale del problema
delle caratteristiche per le coniche d'un piano, base e modello minimo della varietà degli elementi lineari del piano) (1).
Il mio primo lavoro è stato pubblicato negli ? Atti della R. Accademia delle Scienze di Torino ? (vol. XXXV, pag. 774) il
27 maggio 1900. Veramente io avevo già fatto stampare fin dal 1898 mentre ero studente presso una tipografia della mia nativa
Arezzo, una noticina sull'estensione dei teoremi diPascal e diBrianchon. Non sapevo allora che l'estensione era nota. 相似文献
10.
Franca M. Cordero Francesco De Sarlo Alberto Brandi 《Monatshefte für Chemie / Chemical Monthly》2004,40(2):649-669
The review outlines the various different azaheterocycles available from 5-spirocyclopropane isoxazolidines. These compounds can be regarded as versatile direct precursors of tetrahydro-, dihydropyridone and azetidinone derivatives. The current scope and limitations, and the selectivity aspects of the different processes are discussed therein. 相似文献