bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modulares Design in natürlichen und biomimetischen elastischen Materialien
Authors: Kushner Aaron M. , Guan Zhibin 
Published: September 2011

AbstractUnter Verwendung der zwanzig natürlichen Aminosäuren als Grundbausteine haben biologische Systeme während der Jahrmillionen unter evolutionärem und umweltbedingtem Druck stabile und leichte Peptid‐basierte Materialien entwickelt. Diese Materialien übertreffen ihre synthetischen Gegenstücke in mehrfacher Hinsicht: 1) Multifunktionalität/Abstimmbarkeit, 2) Anpassungsfähigkeit/Reizempfindlichkeit, 3) Synthese und Weiterverarbeitung bei Umgebungsbedingungen in wässrigem Medium und 4) Wiederverwertung und biologische Abbaubarkeit. Diese besonderen Eigenschaften können durch eine “Bottom‐up”‐Synthese und die hierarchische Organisation auf verschiedenen Längenskalen erreicht werden. Das Arbeitsgebiet der “Biomimikry” beschäftigt sich damit, die Gestaltungsprinzipien natürlicher Materialien und deren molekulare Bausteine aufzuklären und zu kopieren. Hier beschreiben wir, was bereits über Struktur und molekulare Mechanismen natürlicher polymerer Materialien erforscht wurde, sowie den Fortschritt in Richtung synthetischer “Nachbildungen” dieser bemerkenswerten Systeme.
Modular Design in Natural and Biomimetic Soft Materials
Authors: Kushner Aaron M. , Guan Zhibin 
Published: September 2011

AbstractUnder eons of evolutionary and environmental pressure, biological systems have developed strong and lightweight peptide‐based polymeric materials by using the 20 naturally occurring amino acids as principal monomeric units. These materials outperform their man‐made counterparts in the following ways: 1) multifunctionality/tunability, 2) adaptability/stimuli‐responsiveness, 3) synthesis and processing under ambient and aqueous conditions, and 4) recyclability and biodegradability. The universal design strategy that affords these advanced properties involves “bottom‐up” synthesis and modular, hierarchical organization both within and across multiple length‐scales. The field of “biomimicry”—elucidating and co‐opting nature’s basic material design principles and molecular building blocks—is rapidly evolving. This Review describes what has been discovered about the structure and molecular mechanisms of natural polymeric materials, as well as the progress towards synthetic “mimics” of these remarkable systems.
Effect of addition of glycolysis products of poly(ethyleneterephthalate) wastes to urea‐formaldehyde resin on its adhesion performance to wood substrates and formaldehyde emission
Authors: Essawy Hisham A. , Tawfik Magda E. , Elsayed Nadia H. 
Published: September 2011

AbstractRecycling of poly(ethyleneterephthalate) waste was achieved through glycolysis using diethyleneglycol (DEG) and poly(ethyleneglycol) (PEG 400), which yielded different fractions that exhibited hydroxyl numbers of 174.41 and 54.86 mg of KOH/g, respectively, whereas GPC profiles revealed bimodality in both cases corresponding to Mn values equivalent to 534 and 1648. The products of glycolysis from both cases were individually incorporated as modifiers during the synthesis of urea‐formaldehyde resins from both the basic as well as acidic stages, respectively. It was found that the free formaldehyde level was remarkably decreased for the modified resins while the gel time was slightly affected indicating some activation of the resins. In addition, the adhesion strength of wood joints bonded with the modified resins improved markedly in the dry state while the moisture resistance was significantly fortified with respect to the comparable joints formulated from unmodified resins where instant failure took place within few hours after immersion in water. The shelf life of the resins did not prolong and lasted maximum for about 2 months which was ascribed to the presence of reasonable amount of carboxyl terminal groups at the ends of a minor portion of the glycolyzed products that could actively act to self‐catalyze the polycondensation and crosslinking reactions during storage leading eventually to vitrification of the resin and shortening of shelf life. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Psychoanalysis, the Tyranny of Objectivism, and the Rebellion of the Subjective
Authors: Summers Frank 
Published: September 2011

ABSTRACTThe standard definition of psychology as the behavior of living organisms is subject to scrutiny and found to be untenable. Such a view is self‐contradictory, puts method before subject matter, and misconstrues the very nature of the psychic. The objectivist view is an index of a materialist culture that defines all value, and even all reality, in quantifiable terms. Some of the damaging consequences of this view are presented, and then the phenomenological alternative is proposed. The latter avoids reification of the psyche by identifying human being in Heideggerean terms as Being‐in‐the‐world, or Dasein, Being‐there. This conceptualization provides the basis for understanding human experience by an attitude of openness to the existing subject, precisely the stance of the psychoanalytic clinician. Psychoanalytic therapy, as one of the few bastions left for the study of human subjectivity, constitutes a rebellion against the hegemonic view of reality as quantitative. For that very reason analysis is in a unique position to lead a movement against the dominant ideology of quantification. It is argued that psychoanalysis matters because it is one of the few arenas left in which human subjectivity is appreciated and studied. Copyright © 2011 John Wiley & Sons, Ltd.
Synthetic beta‐K0.33V2O5 Nanorods: A Metal–Insulator Transition in Vanadium Oxide Bronze
Authors: Zhang Xiaodong , Yan Wensheng , Xie Yi 
Published: September 2011

AbstractWe found a linear relationship between the metal–insulator transition (MIT) temperature and the A+ ionic radius of the beta‐A0.33V2O5 bronze family, leading our attention to beta‐K0.33V2O5 which has been neglected for a long time. We have introduced a facile hydrothermal method to obtain the single‐crystalline beta‐K0.33V2O5 nanorods. As expected, both the temperature‐dependence of the resistivity and magnetization demonstrated MITs at about 72 K for beta‐K0.33V2O5, thus matching well with the linear relationship described above. The beta‐K0.33V2O5 was assigned as a new member of the beta‐A0.33V2O5 bronze family for their similar crystal and electronic structures and their MIT property; this addition enriches the beta‐A0.33V2O5 bronze family.
Convergence Properties of Iterative Learning Control Processes in the Sense of the Lebesgue‐P Norm
Authors: Ruan Xiaoe , Bien Z. Zenn , Wang Qi 
Published: September 2011

AbstractThis paper addresses the convergence issue of first‐order and second‐order PD‐type iterative learning control schemes for a type of partially known linear time‐invariant systems. By taking advantage of the generalized Young inequality of convolution integral, the convergence is analyzed in the sense of the Lebesgue‐p norm and the convergence speed is also discussed in terms of Qp factors. Specifically, we find that: (1) the sufficient condition on convergence is dominated not only by the derivative learning gains, along with the system input and output matrices, but also by the proportional learning gains and the system state matrix; (2) the strictly monotone convergence is guaranteed for the first‐order rule while, in the case of the second‐order scheme, the monotonicity is maintained after some finite number of iterations; and (3) the iterative learning process performed by the second‐order learning scheme can be Qp‐faster, Qp‐equivalent, or Qp‐slower than the iterative learning process manipulated by the first‐order rule if the learning gains are appropriately chosen. To manifest the validity and effectiveness of the results, several numerical simulations are conducted.Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Thermal budget control for processes with spike‐shaped temperature profiles: Application to rapid thermal annealing
Authors: Jeng Jyh‐Cheng , Li Bo‐Chi 
Published: September 2011

AbstractThe spike‐shaped temperature profile in thermal treatments is widely used in the IC industry for providing precise thermal budgets. This thermal budget control issue becomes more crucial as the technology node progressively shrinks. Therefore, rapid thermal processing (RTP), such as spike annealing has the ability to yield ultra‐shallow junctions. With its exceptionally stringent performance requirements (for example, high temperature uniformity and high temperature ramp‐up/down rate), temperature control in RTP systems is a challenging task. In this study, a novel methodology for designing a control system to provide a precise thermal budget is presented. By tuning controller parameters and designing the set‐point profile, the method targets thermal budget indices instead of temperature servo control. Two types of controllers, PI and PI 2D, are considered. Practical issues, such as the feasibility range for temperature ramp‐up/down rate and the effect of model mismatch, are also discussed. The results show that the simple PI controller performs well in spike RTP systems.Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Identification and robust control for systems with ellipsoidal parametric uncertainty by convex optimization
Authors: Sadeghzadeh Arash 
Published: September 2011

AbstractIn this paper, sufficient conditions for robust output feedback controller design for systems with ellipsoidal parametric uncertainty are given in terms of solutions to a set of linear matrix inequalities (LMIs) Performance specifications are in terms of combined pole placement with sensitivity function shaping in the H2 or H∞ norm. Furthermore, an optimal input design technique for parameter estimation that is integrated into the robust control design is employed in this paper. This means that performance specifications on the closed‐loop transfer functions are translated into the requirements on the input signal spectrum. The simulation results show the effectiveness of the proposed method.Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Adaptive synchronization of master–slave systems with mixed neutral and discrete time‐delays and nonlinear perturbations
Authors: Karimi Hamid Reza , Zapateiro Mauricio , Luo Ningsu 
Published: September 2011

AbstractThis paper investigates the delay‐dependent adaptive synchronization problem of the master and slave structure of linear systems with both constant neutral and time‐varying discrete time‐delays and nonlinear perturbations based on the Barbalat lemma and matching conditions. An adaption law which includes the master‐slave parameters is obtained by using the Lyapunov functional method and inequality techniques to synchronize the master‐slave systems without the knowledge of upper bounds of perturbation terms. Particularly, it is shown that the synchronization speed can be controlled by adjusting the update gain of the synchronization signal. A numerical example has been given to show the effectiveness of the method.Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
An adaptive output feedback dynamic surface control for a class of nonlinear systems with unknown backlash‐like hysteresis
Authors: Zhang Xu , Lin Yan 
Published: September 2011

AbstractThis paper is devoted to the output feedback control for a class of nonlinear systems with unknown backlash‐like hysteresis at the input. Based on a high‐gain observer, an adaptive dynamic surface control scheme is proposed which is able to mitigate the effect of the hysteresis, to eliminate the explosion of terms inherent in backstepping control, and in particular, by introducing an initialization technique, to guarantee the ∞ performance of the system's tracking error. Another advantage of the proposed scheme is that the adaptive law is needed only at the first design step, which greatly simplifies the design procedure and makes our control easy to implement.Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Formation control of multiple elliptic agents with limited sensing ranges
Authors: Do K. D. 
Published: September 2011

AbstractThis paper presents a design of cooperative controllers that force a group of N mobile agents with an elliptic shape and limited sensing ranges to perform a desired formation and that guarantee no collisions between any agents in the group. The desired formation can be stabilized at feasible reference trajectories with bounded time derivatives. The formation control design is based on explicit algebraic separation conditions between ellipses, root conditions of cubic polynomials, the Lyapunov direct method, and smooth or p‐times differentiable step functions. These functions are incorporated into novel potential functions to solve the collision avoidance problem without the need for switchings despite the agents' limited sensing ranges.Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Redispersion Microreactor System for Phase Transfer‐Catalyzed Esterification
Authors: Jovanović J. , Hengeveld W. , Rebrov E. V. , Nijhuis T. A. , Hessel V. , Schouten J. C. 
Published: September 2011

AbstractAn interdigital mixer‐redispersion capillary assembly was applied to prevent the liquid‐liquid bubbly flow coalescence in microreactors. The redispersion capillary consisted of 1‐mm‐long 0.25 mm inner‐diameter constrictions, placed every 0.50 m along the channel length. The system was tested on the phase transfer‐catalyzed esterification to produce benzyl benzoate. The application of constrictions to prevent coalescence resulted in a better reproducibility and higher conversion compared to a capillary without constrictions. The bubbly flow generated by the interdigital mixer‐redispersion capillary assembly was found to be independent of the redispersion capillary inner diameters (0.50 and 0.75 mm) while being highly dependent on the flow rates. By controlling the total flow rate and the aqueous‐to‐organic ratio, the bubbly flow surface‐to‐volume ratio could be increased up to 230 700 m2m–3. Compared to the conventional phase transfer‐catalyzed esterification, the continuous operation in the interdigital mixer‐redispersion capillary assembly eliminated the use of solvents and bases, removing an energy‐intensive step of distillation while increasing process safety.
Boron/Nitrogen Substitution of the Central Carbon Atoms of the Biphenalenyl Diradical π Dimer: A Novel 2e–12c Bond and Large NLO Responses
Authors: Zhong Rong‐Lin , Zhang Ji , Muhammad Shabbir , Hu Yang‐Yang , Xu Hong‐Liang , Su Zhong‐Min 
Published: September 2011

AbstractOn the basis of the famous staggered biphenalenyl diradical π dimer 1, the eclipsed biphenalenyl (1 a), with no centrosymmetry, was obtained by rotating a layer of 1 by 60° around its central axis. Furthermore, the central carbon atoms of 1 and 1 a were substituted by boron and nitrogen atoms to form 2 and 2 a with a novel 2e–12c bond. We found that the novel 2e–12c bond is formed by the electron pair of the occupied orbital of the phenalenyl monomer substituted by the nitrogen atom and the unoccupied orbital of the phenalenyl monomer substituted by the boron atom. As a result of the novel 2e–12c bond, 2 and 2 a exhibit a fascinating interlayer charge‐transfer transition character, which results in a significant difference in the dipole moments (Δμ) between the ground state and the crucial excited state. The values of Δμ for 2 and 2 a are 6.4315 and 6.9253 Debye, clearly larger than the values of 0 and 0.0015 Debye for 1 and 1 a. Significantly, the boron/nitrogen substitution effect can greatly enhance the first hyperpolarizabilities (β0) of 2 and 2 a with a novel 2e–12c bond compared with 1 and 1 a with a traditional 2e–12c bond: 0 and 19 a.u. for 1 and 1 a are much lower than 3516 and 12272 a.u. for 2 and 2 a. Furthermore, the interaction energies (Eint)of 2 and 2 a are larger than those of 1 and 1 a, which could be considered as a signature of reliability for the newly designed dimers. Our present work will be beneficial for further theoretical and experimental studies on the properties of molecules with the novel 2e–12c bond.
Persistent Hydrogen‐Bonded and Non‐Hydrogen‐Bonded Phenoxyl Radicals
Authors: Wanke Riccardo , Benisvy Laurent , Kuznetsov Maxim L. , Guedes da Silva M. Fátima C. , Pombeiro Armando J. L. 
Published: September 2011

AbstractThe production of stable phenoxyl radicals is undoubtedly a synthetic chemical challenge. Yet it is a useful way to gain information on the properties of the biological tyrosyl radicals. Recently, several persistent phenoxyl radicals have been reported, but only limited synthetic variations could be achieved. Herein, we show that the amide–o‐substituted phenoxyl radical (i.e. with a salicylamide backbone) can be synthesised in a stable manner, thereby permitting easy synthetic modifications to be made through the amide bond. To study the effect of H‐bonding on the properties of the phenolate/phenoxyl radical redox couple, simple H‐bonded and non‐H‐bonded o,p‐tBu‐protected salicylamidate compounds have been prepared. Their redox properties were examined by cyclic voltammetry and showed a fully reversible one‐electron oxidation process to the corresponding phenoxyl radical species. Remarkably, the redox potential appears to be correlated, at least partially, with H‐bond strength, as relatively large differences (ca. 300 mV) in the redox potential between H‐bonded and non‐H‐bonded phenolate salts are observed. The corresponding phenoxyl radicals produced electrochemically are persistent at room temperature for at least an hour; their UV/Vis and EPR characterisation is consistent with that of phenoxyl radicals, which makes them excellent models of biological tyrosyl radicals. The analyses of the experimental data coupled with theoretical calculations indicate that both the deviation from planarity of the amide function and intramolecular H‐bonding influence the oxidation potential of the phenolate. The latter H‐bonding effect appears to be predominantly exerted on the phenolate and not (or only a little) on the phenoxyl radical. Thus, in these systems the H‐bonding energy involved in the phenoxyl radical appears to be relatively small.
Surface Organobarium and Organomagnesium Chemistry on Periodic Mesoporous Silica MCM‐41: Convergent and Sequential Approaches Traced by Molecular Models
Authors: Michel Olaf , König Sonja , Törnroos Karl W. , Maichle‐Mössmer Cäcilia , Anwander Reiner 
Published: September 2011

AbstractThe alkaline earth metal alkyl complexes [Ba(AlEt4)2]n and Mg(AlMe4)2 were directly grafted onto periodic mesoporous silica MCM‐41, which had been dehydroxylated at 270 °C (specific surface area as: 1023 m2 g−1; pore volume Vp: 1.08 cm3 g−1; main pore diameter 3.4 nm). Alternatively, barium alkyl surface species were generated by sequential grafting of MCM‐41 with Ba[N(SiHMe2)2]2(thf)4 and AlEt3 to yield the hybrid material AlEt3@Ba[N(SiHMe2)2]2(thf)4@MCM‐41. For a better understanding of the surface chemistry, AlEt3@MCM‐41 was also accessed. All hybrid materials were analyzed by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, elemental analysis, nitrogen physisorption, and solid‐state NMR spectroscopy; this clearly revealed distinct surface chemistry for the alkylaluminate‐treated materials [Ba(AlEt4)2]@MCM‐41 and Mg(AlMe4)2@MCM‐41. In an attempt to mimic the surface chemistry, the organometallic precursors were treated with HOSi(OtBu)3. The reaction of equimolar amounts of {Ba[N(SiHMe2)2]2}n and HOSi(OtBu)3 produced a mixed silylamido/siloxide cluster of Ba3[OSi(OtBu)3]3[N(SiHMe2)2]3 with bridging‐only siloxide ligands as well as one bridging and two terminal silylamido ligands. The Schlenk equilibrium was found to govern the [Ba(AlEt4)2]n–HOSi(OtBu)3 and Mg(AlMe4)2–HOSi(OtBu)3 reactions, leading to the isolation of complexes of [Ba(AlEt4)2(toluene)]2 and Mg[OSi(OtBu)3)]2(AlMe3)2, respectively. Allowing for a donor‐induced cleavage of Mg(AlMe4)2, the reaction of [MgMe2] with one or two equivalents of HOSi(OtBu)3 was studied. While putative Mg[OSi(OtBu)3](Me) and Mg[OSi(OtBu)3]2 could not be crystallized from the reaction mixtures, cluster complexes Mg5(O)[OSi(OtBu)3]5Me3 and Mg4(OH)2[OSi(OtBu)3]6 could be unambiguously identified by X‐ray crystallography.
Diabetes mellitus and risk of hepatocellular carcinoma: a systematic review and meta‐analysis
Authors: Wang Ping , Kang Donghong , Cao Wei , Wang Yan , Liu Zhiwen 
Published: September 2011

SummaryStudies of diabetes and hepatocellular carcinoma (HCC) yielded inconsistent findings. This meta‐analysis was conducted to examine the association between diabetes and risk of HCC. Studies were identified by searching PUBMED and MEDLINE database up to February 2011. Pooled risk estimates were calculated using the random‐effects model. Potential sources of heterogeneity were explored by subgroup analyses. A total of 17 case‐control studies and 32 cohort studies were included in the meta‐analysis. The combined risk estimate of all studies showed a statistically significant increased risk of HCC prevalence among diabetic individuals (RR = 2.31, 95% CI: 1.87–2.84). The pooled risk estimate of 17 case‐control studies (OR = 2.40, 95% CI: 1.85–3.11) was slightly higher than that from 25 cohort studies (RR = 2.23, 95% CI: 1.68–2.96). Metformin treatment was potentially protective. On the contrary, long duration of diabetes and sulfonylureas or insulin treatment possibly increase HCC risk. Also meta‐analysis of 7 cohort studies found a statistically significant increased risk of HCC mortality (RR = 2.43, 95% CI: 1.66–3.55) for individuals with (versus without) diabetes. This meta‐analysis shows that diabetes is associated with moderately increased risk of HCC prevalence, as well as HCC mortality. Considering the rapidly increasing prevalence of diabetes mellitus, the study underlines the need for cancer prevention in diabetic individuals. Further investigation is needed to focus on the potential mechanism for the pathogenesis of HCC and the link between HCC and different types, severity, treatment and duration of diabetes. Copyright © 2011 John Wiley & Sons, Ltd.