Chain Mode Research Articles

System Dynamics Modelling of Remanufacturing and Recycling Mode Based on Closed-Loop Across-Chain Competition

To face the reality of resources exhaustion, the significance of recycling and remanufacturing in the closed-loop chain has become quite evident. This paper constructs a competitive recycling and remanufacturing model of the closed-loop supply chain through a case study of Midea Corp. and Gree Corp. and explores the impact of two recycling modes on total revenue of the supply chain and market share. The simulation results show that the total revenue of the supply chain will benefit from the increasing coverage points by the third party and the increasing environmental awareness of certain regions. The retailers show more enthusiasm of recycling through certain amendment of the contract between manufacturers and retailers. The time of payment could be shortened in closed loop. Moreover, the improvement of recycling mechanism of the retailers can enlarge the share of supply chain market. Guiding role of the proposed model and the simulation results played in establishing a better supply chain mode is presented.

From SARS to MERS: evidence and speculation.

The Middle East respiratory syndrome coronavirus (MERS-CoV) is a novel zoonotic pathogen. In 2012, the infectious outbreak caused by MERS-CoV in Saudi Arabia has spread to more than 1600 patients in 26 countries, resulting in over 600 deaths.Without a travel history, few clinical and radiological features can reliably differentiate MERS from SARS. But in real world, comparing with SARS, MERS presents more vaguely defined epidemiology, more severe symptoms, and higher case fatality rate. In this review, we summarize the recent findings in the field of MERS-CoV, especially its molecular virology, interspecies mechanisms, clinical features, antiviral therapies, and the further investigation into this disease. As a newly emerging virus, many questions are not fully answered, including the exact mode of transmission chain, geographical distribution, and animal origins. Furthermore, a new protocol needs to be launched to rapidly evaluate the effects of unproven antiviral drugs and vaccine to fasten the clinical application of new drugs.

Lateral entry guidance with no-fly zone constraint

No-fly zones are geographic constraints for the atmospheric entry flight. Two lateral guidance methods are presented for the entry flight constrained by multiple no-fly zones. The first method employs a dynamic heading corridor to control the vehicle's velocity heading angle. The corridor is generated based on a chain mode strategy that takes heading limits for all the no-fly zones and the target into account. The dynamic corridor is adaptively updated during the flight according to the vehicle's state and the actual constraints. The second method is designed based on a waypoint vector which is located between each pair of no-fly zones. This waypoint vector contains both the location and the direction constraints for the flight trajectory. The vehicle is capable of flying the avoidance trajectory by passing through one or more expected waypoints in specified directions. The two guidance methods are finally tested in four entry missions constrained by various no-fly zones. Results indicate that these methods are effective for no-fly zone avoidance missions in both the nominal and dispersed cases.

Weak coupling of pseudoacoustic phonons and magnon dynamics in the incommensurate spin-ladder compound Sr14Cu24O41

Intriguing lattice dynamics has been predicted for aperiodic crystals that contain incommensurate substructures. Here we report inelastic neutron scattering measurements of phonon and magnon dispersions in Sr14Cu24O41, which contains incommensurate one-dimensional (1D) chain and two-dimensional (2D) ladder substructures. Two distinct pseudoacoustic phonon modes, corresponding to the sliding motion of one sublattice against the other, are observed for atomic motions polarized along the incommensurate axis. In the long wavelength limit, it is found that the sliding mode shows a remarkably small energy gap of 1.7-1.9 meV, indicating very weak interactions between the two incommensurate sublattices. The measurements also reveal a gapped and steep linear magnon dispersion of the ladder sublattice. The high group velocity of this magnon branch and weak coupling with acoustic and pseudoacoustic phonons can explain the large magnon thermal conductivity in Sr14Cu24O41 crystals. In addition, the magnon specific heat is determined from the measured total specific heat and phonon density of states, and exhibits a Schottky anomaly due to gapped magnon modes of the spin chains. These findings offer new insights into the phonon and magnon dynamics and thermal transport properties of incommensurate magnetic crystals that contain low-dimensional substructures.

Raman scattering in dried DNA and crystalline amino acids

Raman spectrum characteristics of dried deoxyribonucleic acid (DNA) and two types of crystalline amino acids (L-lysine, D-asparagine) are compared in a wide range of frequencies, including the regions of lattice (7 to 200 cm−1) and intramolecular (200 to 4000 cm−1) vibrations. It is found that the spectral position of the low-frequency band in the Raman spectrum of DNA with a peak near 26 cm−1 correlates with the Raman spectrum of high-Q low-frequency modes that manifest themselves in the crystalline amino acids under investigation. The low-frequency band of DNA refers to a twist-like vibrational mode of nucleobases. The intensities of this DNA mode and the high-Q lattice modes of the crystalline amino acids L-lysine and D-asparagine are several times as high as those of the Raman lines corresponding to the intramolecular modes. Resonant coupling of low-frequency modes of DNA and amino acid molecular chains is analyzed.

Absorptive Capacity as a Mediator: Innovation of Handicraft Exporters in Yogyakarta, Indonesia

AbstractInnovation processes in emerging economies tend to differ from those in developed countries in that a larger share of firms absorb existing knowledge. The paper assesses how firms’ absorptive capacity mediates the impact of global value chains on the innovation of handicraft exports in Yogyakarta, Indonesia. The study draws three conclusions. First, the incremental innovation of craft exporters demands specific but rather mundane absorptive capacities of firms, such as language abilities and capable departments. Second, and contrary to what might be expected, the study finds that the governance modes of global value chains do not significantly affect the level of innovation. Third, a group of traders have the highest level of innovation, the highest level of absorptive capacity, and they positively affect the innovation of suppliers. Overall, the findings show that knowledge diffusion is furthered within an emerging local innovation system.

Automobile chain maintenance parts delivery problem using an improved ant colony algorithm

The mode of automotive maintenance chain is gaining more and more attention in China because of its advantages such as the lower cost, higher speed, higher availability, and strong adaptability. Since the automobile chain maintenance parts delivery problem is a very complex multi-depot vehicle routing problem with time windows, a virtual center depot is assumed and adopted to transfer multi-depot vehicle routing problem with time windows to multi-depot vehicle routing problem with the virtual central depot, which is similar to a vehicle routing problem with time windows. Then an improved ant colony optimization with saving algorithms, mutation operation, and adaptive ant-weight strategy is presented for the multi-depot vehicle routing problem with the virtual central depot. At last, the computational results for benchmark problems indicate that the proposed algorithm is an effective method to solve the multi-depot vehicle routing problem with time windows. Furthermore, the results of an automobile chain maintenance parts delivery problem also indicate that the improved ant colony algorithm is feasible for solving this kind of delivery problem.

Chain mapping approach of Hamiltonian for FMO complex using associated, generalized and exceptional Jacobi polynomials

The excitation energy transfer (EET) in photosynthesis complex has been widely investigated in recent years. However, one of the main problems is simulation of this complex under realistic condition. In this paper by using the associated, generalized and exceptional Jacobi polynomials, firstly, we introduce the spectral density of Fenna–Matthews–Olson (FMO) complex. Afterward, we obtain a map that transforms the Hamiltonian of FMO complex as an open quantum system to a one-dimensional chain of oscillatory modes with only nearest neighbor interaction in which the system is coupled only to first mode of chain. The frequency and coupling strength of each mode can be analytically obtained from recurrence coefficient of mentioned orthogonal polynomials.

Investigation of nonlinear rheological behavior of linear and 3-arm star 1,4-cis-polyisoprene (PI) under medium amplitude oscillatory shear (MAOS) flow via FT-rheology

Monodisperse linear and 3-arm star polyisoprene (PI) melts were investigated under dynamic oscillatory shear flow. Master curves of linear rheological properties, G′ (ω) and G″ (ω), obtained by small amplitude oscillatory shear (SAOS) testing and nonlinear rheological properties, Q0 (ω), obtained by medium amplitude oscillatory shear (MAOS) testing, were created using the same shift factors by applying the time–temperature superposition (TTS) principle. Linear master curves of 3-arm star PIs were broader than those of linear PIs because of the contribution made by an additional relaxation mode due to arm retraction. This difference was clearer in nonlinear master curves. In nonlinear master curves (Q0 (ω)), linear PIs showed only one peak corresponding to relaxation of the backbone chain, whereas two weak local peaks were observed for 3-arm star PIs. One peak at lower frequency reflected backbone relaxation and the other at higher frequency reflected branch relaxation. These findings confirm that Q0 is a highly sensitive parameter for characterizing the effect of one branch by detecting backbone and branch relaxation modes. Based on the hierarchical relaxation concept of branched polymers, three characteristic relaxation times of 3-arm star PIs were determined from a nonlinear master curve: backbone relaxation time (τb) from local maximum Q0 at lower frequency, backbone Rouse time (τR,b) from local minimum Q0, and arm relaxation time (τa) from local maximum Q0 at higher frequency. Backbone relaxation times (τb) from nonlinear master curves almost coincided with linear viscoelastic terminal relaxation times (τw) from linear master curves within the limits imposed by experimental error. These relaxation times, especially τR,b, were used for molecular stress function (MSF) model predictions of 3-arm star PIs as a criterion parameter to determine the terminal relaxation mode of the backbone chain, and τR,b was found to be a reasonable fitting parameter for the MSF model. Fitting results showed that the weak peak arising from the one branch could be quantified using the MSF model. However, both linear and 3-arm star PIs had the same β value of 1, meaning a linear topology without a branch. It was concluded that the effect of only one branch could not be detected using β values. Our results suggest the possibility of using the nonlinear parameter Q0 for determining model parameters for constitutive model equations.

QM/MM simulation of the amide-I band in the Raman spectrum of insulin

ABSTRACTRaman spectroscopy is an effective tool to detect conformational changes and secondary structures of biological molecules. The amide-I band representing the amide carbonyl (C=O) stretching, with smaller contributions of C–N stretching and N–H bending is a signature band for protein secondary structure conformation. We have simulated the Raman spectra of insulin by a hybrid quantum-mechanics and molecular-mechanics (QM/MM) method with an aim to provide an accurate description of the amide-I band. To fulfil this aim we have considered three different QM/MM models with increasingly accurate description of the electrostatic environment for tyrosine (TYR), phenylalanine (PHE) and cystine (CYS) residues of insulin. All three models successfully describe the experimental Raman spectral features associated with the vibrational modes of the amino acid side chains. However, an accurate simulation of the amide-I band is achieved only in one of the three models, where the peptide backbone atoms together with its hydrogen bonding partners are treated with QM method. This work indicates that the accurate treatment of electrostatic interactions of the peptide backbone is crucial for correct simulation of the amide-I region, which acts as a spectral signature of proteins.

File Encryption System Based on Symmetric Key Cryptography

In Today’s scenario, files are not secure. They are fetch by any means of attack by eavesdropper like cracking the pins, crashing the OS by viruses, malwares, and plenty of ways. We today can’t sure that files protection wizards are secure and data can’t be reached to the attacker. But if files are encrypted then even files are accessed original data remains confidential. Therefore, this paper represents the File Encryption System based on Symmetric Key Cryptography. I proposed the strategy to encrypt the files/even multiple files can be encrypted by compressing the files into one ‘rar’ file and it uses Blowfish as encryption/decryption standard and Cipher Block Chain Mode to perform the operations. I implemented compression function for 64-bit Initialization Vector(IV), use CBC mode with Blowfish and RC4 for 256-bit keystream. It is more efficient and secure then other general encryption process

ELECTRICAL AND DIELECTRIC PROPERTIES OF RUBBER

ABSTRACT This review describes electrical and dielectric measurements of rubbery polymers. The interest in the electrical properties is primarily due to the strong effect of conductive fillers, the obvious example being carbon black. Conductivity measurements can be used to probe dispersion and the connectivity of filler particles, both of which exert a significant influence on the mechanical behavior. Dielectric relaxation spectra are used to study the dynamics, including the local segmental dynamics and secondary relaxations, and for certain polymers the global chain modes. A recent development in the application of nonlinear dielectric spectroscopy is briefly discussed.

Universal Trend of the Non-Exponential Rouse Mode Relaxation in Glass-Forming Polymers Systems: Experimental Facts, MD-Simulation Results and a Theoretical Approach Based on a Generalized Langevin Equation

ABSTRACTNowadays there are clear evidences from both experiments and MD-simulations proving that the chain Rouse modes correlation functions are non-exponential in unentangled polymer blends and also in pure polymers at low temperature (with respect to that of the glass transition Tg) even for the long wavelengths modes where local potentials and chain stiffness should not play any role. In a recent paper [S. Arrese-Igor et al, Phys. Rev. Lett.113, 078302 (2014)] it has been proposed that this non-exponential behavior depends on the ratio between the so-called Rouse time - i.e., the characteristic time of the slowest chain mode relaxation - and the time scale of the α-relaxation. This parameter is in some way ‘universal’ in the meaning that it can encode many different experimental situations. In this paper, we show that this behavior can be quantitatively explained in the framework of a theoretical approach based on: (i) a generalized Langevin equation (GLE) formalism and (ii) a memory function which takes into account the effect of collective dynamics on the chain dynamics of a tagged chain and which was constructed taking inspirations from the original ideas of the reptation model proposed by de Gennes.

The growth modes of graphene in the initial stage of a chemical vapor-deposition process

The different growth modes of carbon chains and carbon islands in the initial stage of graphene growth.

Liberalization of the Railway Freight Market in the Context of a Sustainable Transport System

Transport is one of the most important economic sectors; it directly employs around 10 million people and it is concerned in GDP approximately 5% in the European Union (EU). The White Paper of 2011 underlines the need to create new traffic models that will make it possible to meet increasing demands for services through the effective use of various modes of transport and multimodal chains to reduce the external costs of transport. One of the important tools required to ensure sustainable transport is the liberalization of the railway freight transport market, whose main objective is to increase the competitiveness of railway transport reducing the negative impacts of transport on the environment. Actual problems from the view of sustainable transport are mainly those to do with in limited capacity and the level of transport infrastructure and the major differences between the capacity and quality of transport infrastructure in Western and Eastern Europe. The aim of our research is to design measures for the creation of free and undisturbed competition in freight transport to reduce the use of public resources, improving the quality of service even while reducing the social costs of transport. Support for this primary goal will be represented by the definition and description of the complex characteristics of: traffic flows and demand on logistic systems, multimodal chain, business conditions in the transport market, the role of managers of the railway infrastructure in the railway market, system of tolls of the railway infrastructure in terms of minimum access package and additional services in selected EU countries, the social costs of transport, including quantification of external effects, natural and value indicators in relation to the quality of transport processes. The paper deals with research conditions of the liberalization of the railway freight market in the context of a sustainable transport system. We have analysed the charging of the railway infrastructure in the V4 countries and Austria in order to compare charges for model trains. The paper presents a comparative analysis of the number of rail freight operators in individual countries vs rail freight transport performance. Based on this analysis, we investigated whether the liberalization of the rail freight market is reflected in the modal split for the benefit of rail transport.

Strong plasmon coupling in self-assembled superparamagnetic nanoshell chains.

Construction of ordered patterns of plasmonic nanoparticles is greatly important for nanophotonics relevant applications. We have reported a facile and low-cost magnetic field induced self-assembly approach to construct plasmonic superparamagnetic nanoshell (SN) chains up to several hundred micrometers in a few seconds in a large area without templates or other assistance processes. Experimental and theoretical investigations of the near- and far-field optical properties indicate that the super- and sub-radiant modes of the SN chains continuously redshift with the increase of SN number and the Fano resonance emerges in the infinite double- and triple-line SN chains. Strong plasmon coupling effects in the SN chains result in great electric field enhancements at visible and infrared wavelengths, which indicates that these chain structures potentially can be used as a common substrate for both surface enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA) application. This fabrication method also offers a general strategy alternative to top-down processing that enables the construction of nanostructures for metamaterials, electromagnetic energy transport, and optical waveguide.

Stress enhances poly-unsaturation rich lipid accumulation in Chlorella sp. and Chlamydomonas sp.

In the present study, effects of various cultivation conditions on biomass and lipid productivity, detail FAME signature, CO2 biofixation and elemental composition of Chlorella sp. and Chlamydomonas sp. have been investigated. In Chlorella sp., N-depletion has enhanced the lipid productivity by 12.70–14.61%. In Chlamydomonas sp., though the lipid content has increased by 22–26% upon N-depletion, lipid productivity has not changed significantly due to concomitant decrease in biomass productivity by 18–25%. The presence of lipid was also confirmed by FTIR spectroscopic analysis of biomass. The characteristic bands observed at 1744.30 cm−1 (Chlamydomonas sp.) and (Chlorella sp.) were credited to lipids due to C–O mode of the side chain from ester carbonyl group. Extracted lipid was transesterified to FAMEs. Chlorella sp. at N-replete indoor condition has produced the highest weight percentage of C16:0 (26.64%), C18:0 (3.77%) and C18:1 (27.94%). In Chlamydomonas sp., N-replete indoor condition has resulted in maximum content of MUFA (30.12%), LUFA (53.35%), second highest SFA (29.22%) and DUFA (23.23%). Inverse relationship was observed between MUFA and PUFA at all cultivation conditions. In both the microalgae, C16:0, C18:1 (9), C18:2 (9, 12), C18:3 (9, 12, 15) were identified as the major FAMEs which are suitable to be used as biodiesel components.

A perspective on experimental findings and theoretical explanations of novel dynamics at free surface and in freestanding thin films of polystyrene

Most studies of the dynamics at the surface and in thin films of polystyrene (PS) are focused on the change of glass transition temperature from the bulk value. In this perspective, we highlight three new developments in research on the dynamics of PS in high molecular weight (MW) freestanding PS thin films and at the surface of low MW PS. Novel findings from these developments require consideration of viscoelastic mechanisms with length scales longer than the segmental α-relaxation. The first development is the creep compliance measurements of high-MW PS thin films, probing not only the segmental α-relaxation, but also the polymer chain modes at higher compliance levels, including the sub-Rouse modes and the Rouse modes. The compliance data indicate the relaxation times of the sub-Rouse modes are reduced in thinner films like that of the segmental α-relaxation but to a much less extent. The second development is the novel observation of two glass transitions in freestanding polystyrene thin films by ellipsometry. The upper and lower glass transitions occurs, respectively, at temperatures and , both are below the bulk glass transition temperature. While the lower transition at is associated with the segmental α-relaxation, the only viable explanation of the origin of the upper transition at is from another intrinsic viscoelastic mechanism of PS, and not at different location of the film. Supported by various experiments on PS and other polymers, we show that the sub-Rouse modes are cooperative and coupled to density, and hence giving rise to the upper glass transition in freestanding PS films. The sub-Rouse relaxation times will increase on physical ageing, and bring along an increase in density of the freestanding film due to the coupling. This prediction can be checked by performing ageing experiment. The third development is the reduction of viscosity at the free surface of low MW PS. Since viscous flow of low MW PS is definitely carried out by the sub-Rouse modes and not by the segmental α-relaxation, the experimental finding is direct evidence of enhancement of mobility of the sub-Rouse modes by the mitigation of intermolecular coupling at the surface, consistent with the explanations given for the findings in the two other developments. The enhancement of mobility of the sub-Rouse modes occurs simultaneously with the same effect on the segmental α-relaxation. Notwithstanding, at the surface, the observed reduction of viscosity from the sub-Rouse modes is significantly smaller than the reduction of the segmental relaxation time, which is explained semiquantitatively. Altogether, the three recent advances in the study of dynamics of polymer thin films and at the free surface have shown not only the change of the glass transition temperature effected by the segmental α-relaxation is interesting, but also that of the sub-Rouse modes.

Doped copolymer of polyanthranilic acid and o-aminophenol (AA-co-OAP): Synthesis, spectral characterization and the use of the doped copolymer as precursor of α-Fe2O3 nanoparticles

The copolymer of anthranilic acid and o-aminophenol (AA-co-OAP) was synthesized and characterized by IR, UV–Vis. and thermal analyses (TGA). Linear chain mode was suggested for the pure (AA-co-OAP). The effect of inclusion of MnCl2, CoCl2, NiCl2, CuCl2 and FeCl3 on the spectral, thermal and optical properties of AA-co-OAP has been studied. Octahedral stereochemistry was suggested for Fe, Mn and Ni doped AA-co-OAP, while tetrahedral and square-planar geometries were suggested for Co and Cu doped AA-co-OAP, respectively.Fe doped AA-co-OAP has been used as a precursor for α-Fe2O3 nanoparticles by thermal decomposition route at 800 °C. The obtained hematite has been characterized by XRD and TEM. The average size of the prepared nanoparticles was estimated as 34 nm. The optical band gap of the synthesized hematite nanoparticles was measured and compared with the bulk.

Motion mode of poly(lactic acid) chains in film during strain‐induced crystallization

ABSTRACTHow stress and temperature impact the movement of poly(lactic acid) (PLA) chains in the process of tensile film stretching was studied. The motion mode of chains was investigated through the study of the strain‐induced crystallization and orientation through changes in the draw temperature (Td), draw ratio, and draw rate. The crystallinity and orientation degrees of the PLA films were measured by differential scanning calorimetry, Fourier transform infrared spectroscopy, and polarized optical microscopy. According to the competition between the orientation caused by the stretching and relaxation of chains under the temperature field, the motion modes of PLA chains during strain were divided into four types, modes I–IV. When Td was 100°C, the PLA chains acted in mode I, in which the relaxation rate of chains was so fast that no crystallinity or orientation could be obtained. Beyond a draw rate of 20 mm/min at a Td of 90°C, the type of chain movement changed from mode I to II. In mode II, only crystallites could be reserved after unloading. Chains in the PLA film moved in mode III at a Td of 80°C; then, both the crystallization and orientation were enhanced monophonically with increasing draw rate. Beyond the draw rate of 10 mm/min at a Td of 70°C, the orientation rate of chains was much faster than the relaxation one, and the motion mode transformed from mode III to IV. Then, obvious decreases in the crystallinity and orientation were observed with further increases in the draw rate; this resulted from the destruction of the crystallites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42969.