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This article presents an applicable real-time thermal model for the temperature prediction of permanent magnet synchronous motors. The load capacities of most permanent magnet synchronous motors are usually limited by the temperature, and overheating is one of the main reasons for permanent magnet synchronous motors breakdown, so an applicable temperature prediction approach is helpful to improve motor utilization and protect permanent magnet synchronous motors from thermal distortion. Compared with embedding temperature sensors into motor structures, implementing real-time thermal model in motor controllers is a cost-effective and rapid response protection method, but it still faces the challenges on the temperature estimation accuracy, the complexity of the model parameters and the computational efforts. To balance every aspect of these challenges, this article tries a simple real-time thermal model to accurately predict the thermal behavior by elaborately modeling stator core losses and considering motor itself cooling ability. The affections of the motor current and speed on the core losses are analyzed and a polynomial equation is adopted to deal with their dependencies. To simulate the motor speed impact on the cooling ability, motor speed is involved in the variable thermal conductance of the motor housing inside the surroundings by another polynomial equation. This article describes how to get the most parameters of the proposed real-time thermal model through motor basic dimensional information and introduces the test methods employed to determine the parameters of the above two polynomial equations. In the experiments, first the thermal model building process is provided by an actual permanent magnet synchronous motor with two simple tests, and then the online analytical expressions with the obtained parameters are implemented in the drive controller to verify the performance of the proposed real-time thermal model. The results of the performance tests show that the real-time thermal model has a good agreement between estimated and measured temperature values, and its performance can satisfy the most actual applications.

Type 2 diabetes mellitus (T2DM) is characterized by chronic hyperglycemia, damaged insulin secretion and insulin resistance with high morbidity and mortality. Liraglutide (liragl) and insulin are effective hypoglycemic agents used in T2DM treatment. The potential effect of liragl in combination with insulin on T2DM remains unclear. The aim of the current study was to explore effects of liragl combined with insulin on glycolipid metabolism and cardiovascular function in rats with diabetes. A diabetes model was established in Sprague Dawley rats exposed to a high calorie and high sugar diet in conjunction with intraperitoneal injections of streptozotocin. Results indicated that liragl or insulin used alone decreased glucose and elevated insulin and c-peptide levels. However, their combination revealed greater effects. A significant increase in high-density lipoprotein cholesterol levels along with a decrease in total cholesterol, triglycerides and low-density lipoprotein cholesterol were observed in liragl- and insulin-treated rats compared with STZ-induced diabetes rats. Furthermore, co-administration of liragl and insulin significantly decreased sterol regulatory element-binding protein 1 levels and increased adenosine 5'-monophosphate kinase-α1 and carnitine palmitoyltransferase 1 expression. Combining liragl with insulin reduced myocardial hypertrophy level and gaps between cardiomyocytes compared with liragl or insulin treatment alone. Caspase-3 expression was significantly decreased by combination treatment of liragl and insulin. Oxidative damage was significantly decreased by co-administration of liragl and insulin through enhancing superoxide dismutase expression and reducing malondialdehyde. Furthermore, combination of liragl and insulin significantly reduced myocardial enzyme expression, including myoglobin, creatine kinase-muscle/brain and cardiac troponin I. In summary, the current study demonstrated synergistic effects of liragl and insulin injections on a T2DM rat model by maintaining glycolipid metabolism and cardiovascular function.

Two new multidentate ligands 2,6-dimethyl-3,5-dicyano-4-(3-quinolinyl)-1,4-dihydropyridine, L1, and 2,6-diamino-3,5-dicyano-4-(3-quinolinyl)-2,5-heptadiene, L2, incorporating multii-functional groups have been synthesized and reacted with silver(I) salts to give complexes of the types [Ag(L1)(CF3SO3)]n, 1, {[Ag(L1)2](ClO4)}n, 2, and {[Ag2(L2)2](ClO4)2·2CH3CN·H2O}n, 3. All compounds have been characterized by spectroscopic methods and their structures determined by X-ray crystallography. Ligand L1 forms 2-D layer structures in the solid state, while those complexes 1–3 show 0-D molecular complex, 1-D ladder-like chain and 2-D polymeric net forming 3-D supramolecular structures by series N–H⋯O and C-H---X (X = O or F) hydrogen bonds and/or C–H⋯π and π–π interactions. All complexes exhibit emissions which may be tentatively assigned as intra-ligand (IL) π → π∗ transition.

In this study, 2,6-pyridinedimethanol was used as a chain extender to synthesize a new polyurethane, PDM-PU. Further, various amounts of silver nitrate were incorporated to produce PDM-PU/AgNO3 complexes. FT-IR and UV–Vis analyses confirm the formation of complex in the PDM-PU/AgNO3. DSC and DMA results show that the glass transition temperature (T g), dynamic T g and storage modulus at 25 °C of the PDM-PU/AgNO3 complexes increase with increasing AgNO3 content. This is due to the formation of complex structure that can restrict the segmental motion of polymer chains. The TGA and stress–strain test results show that the thermal decomposition temperature, tensile strength and elongation at break increase with the AgNO3 content initially. Then, they decrease inversely. This indicates that the formation of complex structure raises these properties when the AgNO3 content is below certain value. But as more coordinate bonds were formed, the specimens become brittle. In addition, the crosslink effect caused by coordinate bonds inhibits the dissolution of polymer chains and thereby reduces the swelling degree of the complexes in solvent. Furthermore, AgNO3 imparts antibacterial activity against S. aureus and K. pneumoniae to the complexes

The existence of the resonance is usually a trouble causing instability for most elastic drive systems. Generally, the measurement of original resonance of load side in a drive system is a direct solution for resonance suppression, but exact data are difficult to come by, such as torsional torque, load speed and disturbance torque. Therefore, a developed method for resonance suppression based on adaptive filtered x-least mean square algorithm with improved convergence is presented in this research. The proposed method obtains the resonance iteratively and reduces the significant resonance oscillations through a finite impulse response filter adapted by the least mean square error principle. In order to tackle the convergence speed problem caused by the high dynamics of the forward path model, another finite impulse response filter is inserted into the control structure to smooth the current control reference signal and the speed error signal, so that the dynamics features of the forward path model are improved. Furthermore, a filtered x-least mean square control structure for elastic drive systems is also developed. From the simulation and experimental results, the resonance is more effectively suppressed with proposed modified filtered x-least mean square structure compared with notch filters, and the inserted finite impulse response improves the convergence speed.

This paper proposes a complete real-time Ethernet (RTE) solution including master and slave controllers for numerical control (NC) systems. To meet the development tendency of NC systems moving toward multi-axis coordination, high speed and high precision, one type of RTE architecture is built up with a dual ring topology. The function blocks of master/slave nodes are designed to realize the real-time communication capabilities using embedded CPU and field programmable gate array (FPGA) technologies. To reduce the minimum achievable cycle time, a cut-through transmission mechanism is employed to decrease the process latency at slave nodes, and the synchronization frame is optimized to shorten the frame duration. In order to synchronize the nodes of RTE-based NC systems accurately, a time synchronization strategy is scheduled and a proportion-integration (PI)-based phase-locked loop (PLL) is designed to keep the master clock and the slave clocks in step stably. The theoretical analysis and experimental results show that the proposed RTE solution can achieve good real-time performance with low process latency and high time-synchronization accuracy, which satisfies the real-time communication requirements of RTE-based NC systems in an economical way.

This paper proposes an advanced M/T method called Relay-style Digital Speed Measurement Method. Its speed measurement is triggered by encoder pulse signals, which simplifies the complexity of processing incapability of synchronization in the classical method, and it makes actual sampling point always occur before the periodic sampling point in relay-style, which achieves the continuous dynamic iterative measurement with high accuracy in a wide speed range. Through counting the overflow pulses of time counter by software, the minimally measurable speed can be effectively extended to an extremely low level without adding any hardware. In addition, by utilizing the information in speed measurement and subdividing dynamic position by time according to its corresponding relationship with time, Dynamic Position Subdivision Method is achieved to improve the feedback resolution of dynamic position. Finally, the experimental results show that Relay-style Digital Speed Measurement Method can obtain high accuracy than classical method in a wide speed range even though at a very low speed Dynamic Position Subdivision Method is helpful to reduce the fluctuations of the position control.

The syntheses, structures and properties of the complexes [CdBr2(L)2·4H2O]n [L = 2,6-dimethyl-3,5-dicyano-4-(4-pyridyl)-1,4-dihydropyridine], 1 and [Cd(SCN)2(L)2(H2O)]n, 2, are reported. In polymeric complexes 1 — 2, the L ligands bridge the metal centers through the pyrimidyl and cyano nitrogen atoms forming 1-D double-stranded chain and zigzag chain, respectively. The L ligands in complex 1 act as κ1, κ1-bidentate bridging ligand, whereas the L ligands in complex 2 act as κ1-monodentae and κ1, κ1-bidentate bridging ligand. The molecules of these complexes are interlinked through various weak interactions that form the packed structure. All the complexes exhibit emissions which may be tentatively assigned as intraligand (IL) ππ* transitions.

Changes in the overall mass transfer coefficient (KOL) of several volatile organic compounds (VOCs) in surfactant (Triton X-100, Triton X-305, and Triton X-405) solutions are investigated. Different surfactant concentrations, from below to above the critical micelle concentration (CMC), are used to examine the possible inhibition effects on the volatilization of VOCs. The volatilization reduction (or the decrease in the KOL value) of the monoaromatic solutes from the surfactant solutions is considered to be a result of the effects of solubility enhancement and gas–liquid interface hindrance. For the solubility enhancement effect, the extent of volatilization reduction would generally be larger when a surfactant contains less polar ethylene oxide (EO) and when a monoaromatic compound has lower water solubility. On the other hand, gas–liquid interface hindrance may inhibit the volatilization of VOCs due to the aggregation of surfactants at the interface. Both the two-film and surface-depletion rate-limiting (SDRL) models are applied to elucidate the volatilization reduction of VOCs in surfactant solutions. © 2007 Elsevier B.V. All rights reserved.

BACKGROUND: Biosorption of heavy metals from aqueous solution by modified activated carbon with Phanerochaete chrysosporium immobilised in Ca-alginate beads was investigated using a batch system and comparison of linear and nonlinear methods. RESULTS: The amount of Cu(II), Zn(II) and Pb(II) ion sorption by the beads was as follows: activated carbon with P. chrysosporium immobilised in Ca-alginate beads (ACFCA) (193.4, 181.8, 136.6 mg g−1) > activated carbon immobilised in Ca-alginate beads (ACCA) (174.8, 162.0, 130.7 mg g−1) > P. chrysosporium (F) (148.8, 125.6, 120.4 mg g−1) > activated carbon (AC) (138.8, 112.3, 109.3 mg g−1) > plain Ca-alginate beads (PCA) (125.4, 105.2, 98.2 mg g−1). The widely used Langmuir and Freundlich isotherm models were utilised to describe the biosorption equilibrium process. CONCLUSION: The results of this study suggest that the immobilisation of modified activated carbon with P. chrysosporium in Ca-alginate beads is suitable for a batch system. The isotherm parameters were estimated using linear and nonlinear regression analyses. The surface charge density of the biosorbents varied with the pH of the medium; the maximum biosorption of heavy metal ions on the biosorbents was obtained when the pH was between 5.6 and 7.4. Copyright © 2008 Society of Chemical Industry

In the title coordination polymer, [Ag(C10H6NO2)] n , the AgI cation is coordinated by two O atoms and one N atom from three 6-quinolinecarboxylate anions in a distorted T-shaped AgNO2 geometry, in which the O—Ag—O angle is 160.44 (9)°. The 6-quinolinecarboxylate anion bridges three Ag+ cations, forming a nearly planar polymeric sheet parallel to (101). The distance between Ag+ cations bridged by the carboxyl group is 2.9200 (5) Å. In the crystal, π–π stacking is observed between parallel quinoline ring systems, the centroid–centroid distance being 3.7735 (16) Å.

In the title coordination polymer, {[Ag(C(12)H(20)N(2)O(2))]ClO(4)·0.5H(2)O}(n), the Ag(I) cation is coordinated by two N atoms from two 1,2-bis-(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl)ethane (L) ligands in a nearly linear geometry [N-Ag-N = 171.07 (8)°]. The L ligand bridges adjacent Ag(+) cations, forming a polymeric chain running along the c axis. The lattice water mol-ecule is situated on a twofold rotation axis, and links to the perchlorate anion via an O-H⋯O hydrogen bond. The long Ag⋯O separation of 3.200 (4) Å indicates a weak inter-action between the perchlorate anion and the Ag(I) cation. Weak C-H⋯O hydrogen bonding occurs between the chain and the lattice water mol-ecule and between the chain and perchlorate anions. Both five-membered rings of the L ligand display envelope conformations; in one five-membered ring, the flap C atom is disordered on opposite sides of the ring with occupancies of 0.65 and 0.35.

The title tetra-nuclear Cu(II) complex, [Cu(4)(C(12)H(12)N(2)O(2))(4)(CH(3)O)(4)(ClO(4))(2)](ClO(4))(2), is located around an inversion center. Each Cu(II) atom is coordinated by two cis-O atoms from two bridging methano-late anions and two cis-N atoms from two bridging 1,4-bis-(4,5-dihydro-1,3-oxazol-2-yl)benzene (L) ligands in the basal plane, and is further coordinated by one O atom of the bridging perchlorate anion, forming a distorted square-pyramidal geometry. The Cu⋯Cu separations in the recta-ngular core are 2.9878 (11) and 6.974 (1) Å. In the asymmetric unit, there are two L ligands with a syn conformation. In one L ligand, the dihedral angles between the central benzene ring and the terminal 4,5-dihydro-1,3-oxazol-2-yl mean planes are 22.1 (4) and 33.1 (4)°, and in the other L ligand the corresponding dihedral angles are 29.3 (4) and 29.9 (4)°. The uncoordinated perchlorate anion is linked with the complex mol-ecules via weak C-H⋯O hydrogen bonds.