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n-Alkanes have been widely used as phase change materials (PCMs) for thermal energy storage applications because of their exceptional phase transition performance, high chemical stability, long term cyclic stability and non-toxicity. However, the thermodynamic properties, especially heat capacity, of n-alkanes have rarely been comprehensively investigated in a wide temperature range, which would be insufficient for design and utilization of n-alkanes-based thermal energy storage techniques. In this study, the thermal properties of n-alkanes (C18H38-C22H46), such as thermal stability, thermal conductivity, phase transition temperature and enthalpy were systematically studied by different thermal analysis and calorimetry methods, and compared with previous results. Thermodynamic property of these n-alkanes was studied in a wide temperature range from 1.9 to 370 K using a combined relaxation (Physical Property Measurement System, PPMS), differential scanning and adiabatic calorimetry method, and the corresponding thermodynamic functions, such as entropy and enthalpy, were calculated based on the heat capacity curve fitting. Most importantly, the heat capacities and related thermodynamic functions of n-heneicosane and n-docosane were reported for the first time in this work, as far as we know. This research work would provide accurate and reliable thermodynamic properties for further study of n-alkanes-based PCMs for thermal energy storage applications.

Acute Kidney Injury (AKI) is a clinical syndrome characterized by rapid renal deterioration with high morbidity and mortality. Renal reperfusion (IRI), renal toxicity and sepsis are the main causes of AKI. IRI is one of the main causes of acute kidney injury in clinic, accounting for 75% of all the causes of AKI [1]. The fatality rate of AKI caused by IRI is high, and the surviving patients may leave chronic renal impairment with different degrees [2]. A number of studies have shown that ischemia-reperfusion injury leading to renal dysfunction is directly related to oxidative stress, and the inhibition of oxidative stress through nod-like/toll-like signaling pathway can reduce acute renal injury. This review summarizes the research progress in regulating oxidative stress and the relationship between innate immune receptors and acute renal injury.

MicroRNAs (miRs) are inner regulatory RNAs mainly by regulating expression of genes at the posttranscriptional level. To investigate the regulatory function of Bombyx mori (B. mori) fibroin protein genes, the mRNA 3'-untranslated region (3'-UTR) of fibroin light chain gene (BmFib-L) was used as the target and one miRNA, miR-2805 was predicted by using the Software. miR-2805 expression plasmid pcDNA3.0[ie1-egfp-pre-miR-2805-SV40] and BmFib-L 3'-UTR plasmid pGL3.0[A3-luc-Fib-L-3'-UTR-SV40] were constructed, respectively. The mentioned plasmids were cotransfected in BmN cells, and the regulatory function of miR-2805 on BmFib-L was detected by assay of dual luciferase activities, as well as synthesized mimic and inhibitor of miR-2805. The results revealed that miR-2805 significantly downregulated the expression of BmFib-L in BmN cells. To validate the function of miR-2805 in vivo, cultured silk glands or larvae were injected with solution containing pcDNA3.0[ie1-egfp-SV40], pcDNA3.0[ie1-egfp-pre-miR-2805-SV40], mimic, inhibitor respectively. BmFib-L expression was analyzed by quantitative reverse transcription polymerase chain reaction using total RNAs extracted from silk glands. The results showed that miR-2805 significantly upregulated the expression of BmFib-L in both cultured tissues and individuals. To find out how miR-2805 differentially regulates BmFib-L expression in cells and tissues or individuals, we analyzed the expression level of transcription factors (TFs) involved in expression of silk protein genes. The results showed that miR-2805 upregulated the expression of TFs BmAwh and Bmdimm. These results suggest that miR-2805 may up-regulate the expression of BmFib-L interaction with BmAwh and/or Bmdimm in vivo. These findings are beneficial to clarify the molecular mechanism of miRNAs in regulating B. mori silk protein biosynthesis.

Phase change materials (PCMs) generally offer high latent heats for a wide range of thermal energy storage technologies. As typical organic PCMs, polyethylene glycol (PEG) has been widely studied due to their high latent enthalpy, non-toxic and non-corrosive natures. However, the thermal properties especially the heat capacities of PEG, which would play a vital role in theoretically and technically investigating PCM thermal performance, have never been studied in a wide temperature region. Herein, we reported the heat capacities of PEG samples with the molar massvarying from 1000 to 20,000 for the first time in the temperature range from (1.9 to 400) K using a combination method of Physical Property Measurement System (PPMS) and differential scanning calorimeter (DSC). Furthermore, the standard molar heat capacity, entropy and enthalpy at 298.15 K and 0.1 MPa were calculated based on the heat capacity curve fitting. Meanwhile, the phase transition temperature and enthalpy, thermal conductivity and thermal stability of these PEG samples were measured using various thermal analysis methods, and these thermal properties were also compared with the previous results.

Four Zn, Cd and Mn based 1,10-phenanthroline and halogenated benzoic acid coordination compounds, formulated as Zn2II(H2O)3(phen)(SO4)·H2O (1, phen = 1,10-phenanthroline), ZnII(phen)(L2)2(H2O) (2, L2 = 2-chloro-4-fluorobenzoic acid), MnIV(phen)(L1)4 (3, L1 = 2-Chloro-4,5-difluorobenzoic acid) and CdII(phen)2(NO3)2 (4), were successfully synthesized and structurally characterized. The low temperature heat capacities of these four compounds were further investigated using a Physical Property Measurement System calorimetric method. The experimental heat capacities were fitted to a series of theoretical and empirical heat capacity models, and the corresponding thermodynamic functions were calculated in the temperature range from (0 to 300) K based on these models and fitting parameters. The low temperature fits indicated that compound 1 can be modeled using only lattice heat capacity contribution, compound 3 modeled using lattice and A-2 term or Schottky heat capacity contributions, and compound 2 and 4 modeled using contributions from lattice, vacancies and one-dimensional phonons with a finite energy onset or gap.

A new chiral mononuclear iron(II) compound, formulated as {[Fe(ACBP)3]·(ClO4)} (1, ACBP = (S,S)-3,3′-(1,2-dimethylpropanedioxy)-2,2′-bipyridine), has been synthesized and structurally characterized. The magnetic study revealed that compound 1 possesses antiferromagnetic exchange interactions between Fe(II) ions through the hydrogen bonds. The low-temperature heat capacity of compound 1 was measured in the temperature range from 1.9 to 300 K using the heat capacity option of a Quantum Design Physical Property Measurement System (PPMS). Additionally, the thermodynamic functions in the experimental temperature range have been derived by fitting the heat capacity data to a series of theoretical and empirical models. The standard molar heat capacity, entropy and enthalpy of compound 1 at 298.15 K and 0.1 MPa have been determined to be $$C_{\text{p,m}}^{\text{o}}$$ = (1036.9 ± 10.4) J mol−1 K−1, $$S_{\text{m}}^{\text{o}}$$ = (1059.6 ± 10.6) J mol−1 K−1 and $$H_{\text{m}}^{\text{o}}$$ = (160.29 ± 1.60) kJ mol−1, respectively.

Low temperature calorimetry is an experimental method of heat capacity measurements, and heat capacity is one of the most important and fundamental thermodynamic properties of substances. The heat capacity can provide an average evaluation of the thermal property of a sample since it is a bulk property of substances. In the other hand, the condensed states of substances could be mainly controlled by the molecular motions, intermolecular interactions, and interplay among molecular structures. The physical property reflected in a material may be closely related to the energy changes in these three factors, which can be directly observed in a heat capacity curve. Therefore, low temperature calorimetry has been used not only to obtain heat capacity, entropy, enthalpy and Gibbs free energy, but also to investigate and understand lattice vibrations, metals, superconductivity, electronic and nuclear magnetism, dilute magnetic systems and structural transitions. In this review, we have presented the concept of low temperature calorimetry and its applications in the related field of material researches, such as nano-materials, magnetic materials, ferroelectric materials, phase change materials and other materials.

Polyethylene glycol form-stable phase change materials (PEG FSPCMs) have received much attention in recent years for thermal energy storage applications due to their remarkable thermal properties. However, the conventional synthesis of PEG FSPCMs usually employed chemical grade regents as starting materials, which is unlikely suitable for large-scale industrial preparation of PCMs. In the present work, silicagel industrial wastes were employed as starting materials for the first time to synthesize a polyethylene glycol/silica-hydroxyl compound (PEG/SHC) form-stable phase change material using a facile sol-gel method. The morphology and chemical compatibility were characterized using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The thermal energy storage performance was evaluated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), thermal constants analysis, respectively. The results indicated that the PEG was encapsulated in the SHC matrix through a physical interaction, and the weight fraction of PEG in the FSPCM could be as high as 80% with no significant leaking liquid observed. The thermal energy storage capacity in this FSPCM was found to be (59.38–132.4) J/g and (63.56–133.4) J/g in the melting and crystallization process, respectively, as the loaded PEG weight fraction ranging from 50% to 80%. The thermal conductivity of the FSPCM enhanced by the SHC matrix was determined to be as high as 30% compared with that of the pure PEG. Additionally, the FSPCM synthesized in this method could maintain a stable thermal property during the heating/cooling cycles. On the basis of these results, it was demonstrated that the sol-gel method developed in this work could not only obtain PEG based FSPCMs with good performance for thermal energy storage, but also propose an effective way of producing economic benefits by reusing silicagel industrial wastes.

Two novel mononuclear compounds, formulated as [Co(phen)(pae)(H2O)3] ∙ H2O (1) and [Ni(phen)(pae) (H2O)3] ∙ H2O (2) (phen = 1,10-phenanthroline, pae = o-pthalic acid), has been synthesized and structurally characterized. The magnetic measurement revealed that compound 1 and 2 could possess antiferromagnetic exchange interactions between CoII/NiII ions through the hydrogen bonds-bridging. The low temperature heat capacity of compound 1 and 2 were measured using the heat capacity option of a Quantum Design Physical Property Measurement System (PPMS) in the temperature range between (1.9–300) K. The measured heat capacities were fitted to a series of theoretical and empirical models, and the corresponding thermodynamic functions were consequently calculated based on the fitting parameters. Moreover, the heat capacities of these two compounds behave an upturn below 10 K, which could be attributed to the Schottky effect occurring at this low temperature region.

The heat capacities of d-ribose and d-mannose have been studied over the temperature range from 1.9 to 440 K for the first time using a combination of Quantum Design Physical Property Measurement System and a differential scanning calorimeter. The purity, crystal phase and thermal stability of these two compounds have been characterized using HPLC, XRD and TG–DTA techniques, respectively. The heat capacities of d-Mannose have been found to be larger than those of d-ribose due to its larger molecular weight, and the solid–liquid transition due to the sample melting has also been detected in the heat capacity curve. The heat capacities of these two compounds have been fitted to a series of theoretical models and empirical equations in the entire experimental temperature region, and the corresponding thermodynamic functions have been derived based on the curve fitting in the temperature range from 0 to 440 K. Moreover, the phase transition enthalpy and melting temperature of these two compounds have also been determined from the heat flows obtained in DSC measurements.

We found a new way to prove the interaction between the two components in polyaniline (PANI-DTA)/La composites by studying the specific heat. It is firstly found that PANI-DTA has a phase transition peak at −50 °C. The composites (PLa) have no phase transition at −50 °C, so the thermal, magnetic and electrochemical properties are different from PANI-DTA. The heat capacities of the composites are higher than that of PANI-DTA and La complex. the magnetic field dependence of magnetization (M–H) curves of PANI-DTA and PLa-2 exhibit saturation magnetization and a hysteresis loop. The electrochemical performance of the composites are greatly improved compared with PANI-DTA and La complex.

In the bivoltine strain of the silkworm, Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause ability is determined by the environmental condition such as temperature and lightness that mothers experience during their own embryonic development. Diapause preparation is a crucial phase of this process; diapause-destined individuals undergo a series of preparatory events before the entry into developmental arrest. However, the molecular regulatory mechanisms of diapause preparation have largely remained unknown. In the present study, we sequenced the transcriptome of bivoltine silkworm Qiufeng's ovaries resulted in laying of diapause destined or non-diapause eggs, using high-throughput RNA-Seq technology. Differential expression analyses identified 183 genes with higher expression, and 106 with lower expression under diapause-inducing conditions. GO and KEGG analysis revealed that the enrichment of several functional terms related to peroxisome, glycerolipid metabolism, steroid biosynthesis, longevity regulating pathway - multiple species, three signaling transductions, insect hormone biosynthesis, and cytoskeleton components. We conducted a detailed comparison of transcript profile data of ovaries from diapause-inducing and non-diapause conditions, the results imply up-regulation of peroxisomal metabolism, triacylglycerides accumulation, cryoprotectant production, and ecdysteroid biosynthesis in diapause-inducing group. Differential expression of genes related to actin cytoskeleton implies the occurrence of shifts in cellular structure and composition between diapause-inducing and non-diapause-inducing groups. The Hippo and FOXO signaling pathways may play an important role in preparing for entering diapause. This study provides an insight into the molecular events of insect diapause, in particular for the preparatory phase.

In recent years, sugar alcohols have attracted much attention due to their remarkable phase change properties for thermal energy storage applications. The thermodynamic properties especially the heat capacities would play a crucial role in theoretically and technically investigating the energy storage performance for sugar alcohols. However, as far as we known, the heat capacities of sugar alcohols have never been studied in a wide temperature region. In this study, we have measured the heat capacities of six sugar alcohols of D-mannitol, Myo-Inositol, xylitol, D-arabinitol, L-arabinitol and erythritol in the temperature range from T = (1.9 to 550) K for the first time using a combination of Physical Property Measurement System and differential scanning calorimeter. Based on the heat capacity curve fitting, the standard molar heat capacity, entropy and enthalpy at 298.15 K and 0.1 MPa, and melting temperature and transition enthalpy in the solid–liquid phase transition region were consequently obtained for these sugar alcohols. Moreover, the heat capacity and phase transition properties obtained in this work were also compared with previous results reported in literature.

BaZrO3 and PbZrO3 are both technologically important functional materials particularly with attracting paraelectric and antiferroelectric properties, respectively. However, the current heat capacity studies on these two compounds are insufficient to understand their intrinsic chemical or physical property on thermodynamics. Herein, we reported heat capacities of BaZrO3 and PbZrO3 measured using a relaxation calorimeter equipped on the Physical Property Measurement System in the temperature range from (1.9 to 300) K. The heat capacity data was fitted to a series of theoretical and empirical models, and the corresponding thermodynamic functions were calculated in the range from (0 to 300) K. The heat capacity contributions were extracted using the theoretical model and fitting parameters, revealing that the unusual large heat capacity of BaZrO3 compared with that of PbZrO3 below about 2.5 K is likely due to the dominant linear heat capacity contribution. Also, the heat capacity of BaZrO3 was compared with those previously reported in literate, and most importantly, the heat capacity of PbZrO3 is the first time reported in the temperature region from (40 to 300) K in this work, as far as we know.

Metal-organic coordination compounds have been extensively concerned in recent years due to their attracting chemical and physical properties. However, their thermodynamic properties have not been well investigated compared with the other properties, which would limit understanding their relationship between molecular structure and functional performance from a basic thermodynamic view. In the present work, two crystalline compounds of Co3(BTC)2·12H2O (1) and Ni3(BTC)2·12H2O (2) (BTC = 1,3,5- benzenetricarboxylate) have been designed and synthesized using a solvothermal method. The variable-temperature magnetic susceptibilities of these two compounds have been measured and the results revealed that compounds 1 and 2 possessed antiferromagnetic interaction between CoII/NiII ions. Low temperature heat capacities of these two compounds have been measured using a heat capacity option of Physical Property Measurement System in the temperature range from (1.9 to 300) K, and a Schottky effect has been revealed in the heat capacity curve below 10 K. The experimental heat capacity data have been fitted to a series of theoretical and empirical heat capacity models, and the corresponding thermodynamic functions such as enthalpy and entropy have been calculated in the temperature range from (0–300) K based on these models and fitting parameters. Also, the entire Schottky effect peak has been well presented in the heat capacity curve using these fitted heat capacities. The thermodynamic properties obtained in this work may provide significant thermodynamic basis for further investigating the related functional properties of these two compounds.

Complex [Cu(μ-Gly)Im(ClO4)]n(Im = imidazole, and Gly = glycine) with μ-glycine-briged copper (II) chain, containing six-coordination distorted elongated octahedron, was synthesized and characterized. The complex belongs to space group P 21/c measured by X-ray single crystal diffraction. In the cluster, each Cu2+ ion are six-coordination by one nitrogen atom and two oxygen atoms of glycine, one nitrogen atoms of imidazole, and two of oxygen atoms of two perchlorate. Each Cu2+ ion has an N2O4 donor set, which forms the distorted elongated octahedron due to the Jahn–Teller (JT) effect. The magnetic and thermodynamic properties were researched. Magnetic susceptibilities of the complex showed that ferromagnetic interactions occurred between the Cu (II) atoms. The Curie–Weiss constant C = 0.565 cm3 K·mol−1 and the Weiss constant θ = 1.0585 K were given by the Curie-Weiss law The ferromagnetic nature of the interaction could be deduced as the exchange pathway of Cu O C O Cu, which involved an equatorial position at one copper (II) ion and an axial position of the nearest copper (II). The complex decomposed from 511 to 538 K as two steps.

We report the results of the study of thermodynamic properties for two difluorooxymethylene-bridged fluorinated liquid crystals. Isobaric heat capacities of the compounds were measured using a Quantum Design Physical Properties Measurement System with heat capacity measurement in the range of 1.9–300 K. Heat capacities of two compounds increased with the temperature increment, and no any thermal anomalies were observed in the whole temperature region, and also the heat capacity values of 5-CCXB(F,F)-F are larger than that of 3-CCXB(F,F)-F due to molecular weight difference even though they are homologs. Standard thermodynamic properties of the liquid crystals were evaluated from the experimental heat capacity temperature dependencies. From the heat capacity results, the standard molar entropies and enthalpies at 298.15 K were determined to be (657.32 ± 6.57), (741.81 ± 7.42) J K−1 mol−1 and (97.17 ± 0.97), (108.89 ± 1.09) kJ K−1 mol−1 for n-CCXB(F,F)-F (n = 3, 5), respectively. Finally, the phase transition sequences and thermodynamical stability of these two fluorinated liquid crystals were performed by differential scanning calorimetry measurements in the temperature range of 253–373 K.

The prediction of future states, be it of daily events or complex dynamical systems, has always been a challenging topic in the application of probability theory into real life. The benefit of such predictions based on current conditions, and independent of the past, is far-reaching and manifests itself in multiple areas such as transport, biology and economics-areas closely linked to our everyday life. Yet, the study of this topic has not been easy due to the lack of access to vital data of dynamical systems. In this paper, we propose a revolutionary method of studying such systems, through the application of Markov chains into MOBA online games. Using this complex game as a simulation of dynamical systems and an easy source of data, we aim to predict the movement of a game character based on its present position, using the model constructed with Markov chains theory. Through careful experiments, comparing recorded and expected results, and critical evaluation of the method used, we have proven that Markov chains can be effectively applied to yield an accurate prediction of the future state. And with this, we wish to have shed some light on devising innovative ideas on examining dynamical systems, as well as the potential of improving dynamical systems that will benefit the larger society.

Fatty alcohols (FAs) have been widely studied as typical phase-change materials for their high latent heat, low undercooling, non-toxicity, and low cost in thermal energy storage applications. The thermal properties, especially the heat capacity, play a vital role in designing-related energy storage techniques. However, there are few studies on the thermal properties of FAs systematically investigated in a wide temperature region, which greatly limit their application in thermal energy storage field. In this study, the thermal properties of even-numbered FAs (C12H25OH-C18H37OH), such as thermal stability, thermal conductivity, phase transition temperature, and enthalpy have been systematically investigated using a combination of various thermal analysis and calorimetry methods. The corresponding thermodynamic functions such as the standard molar heat capacity, entropy, and enthalpy at 273.15 K and 0.1 MPa have been calculated based on the heat capacity curve fitting. Most importantly, the heat capacities of 1-tetradecanol and 1-hexadecanol are reported for the first time in the wide temperature range of 1.9–370 K. Furthermore, by fitting the heat capacities of FAs, a function of molar heat capacities (Cp) related to the number of carbon atoms (n) and temperature (T) has been established, which can express the heat capacity of FAs between C12H25OH and C22H45OH reasonably in the temperature region of 50–240 K. This work provides accurate and systematic thermodynamic data of FA samples for the future study on their thermodynamic property and related processing design of thermal energy storage application.

The present study presented the extraction and purification of polysaccharides from artificially cultured Cordyceps cicadae and wild Cordyceps cicadae by pre-soaking ultrasonic water extraction. The effects of different concentrations of polysaccharides on proliferation and cytotoxicity of Hela cells were detected by MTT and LDH methods. The results showed that the proliferation of Hela cells was inhibited by polysaccharides treatment (25 μg/mL-1600 μg/mL). The results of flow cytometry further confirmed that polysaccharides blocked the cell cycle in the S phase and promoted apoptosis. RT-qPCR and Western Blot were used to study the mRNA and protein expression of genes related to cell cycle and apoptosis signaling pathway. The results showed that polysaccharides treatment inhibited the expression of Cyclin E, Cyclin A and CDK2 and up regulated the expression of P53. Further, activation of Caspase cascade reaction, up regulation of death receptor, and the ratio of pro-apoptotic factor/anti-apoptotic factors, thus caused the cell cycle arrest and induced the apoptosis. The above research results lay a foundation for extending the anti-cancer effects of natural plant resources with low toxicity and high efficiency.

Novel polyaniline/gadolinium (PANI/Gd) composites were successfully synthesized by “in-situ” polymerization at the presence of rare earth Gd coordination complex and D-tartaric acid (an a dopant). It is rarely to find the studies on related field to add rare earth Gd coordination complex as fillers. Fourier transform infrared (FTIR) spectra, X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to examine the structure and surface appearance characterization of materials. The thermal stability performance of composites was investigated by thermogravimetry and derivative thermogravimetry (TG-DTG). Electrochemical performance was measured by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge–discharge test. The magnetic property was investigated by physical property measurement system (PPMS). The structure and surface appearance characterization and the magnetic properties jointly demonstrate the polymerization of rare earth Gd coordination complex and PANI–D-tartrate (DTA) not only simple physical mixing but also chemical mixing. TG-DTG analysis suggests that thermal stability of PANI/Gd composites is higher than that of PANI–DTA. Electrochemical performance tests and SEM indicate that the composite (PANI/Gd = 3.3:1,mass ratio) has the most regular morphology and best specific capacitance. The magnetization of the composite (PANI/Gd = 3.3:1,mass ratio)is evidently smaller compared with PANI–DTA and rare earth Gd coordination complex. Copyright © 2016 John Wiley & Sons, Ltd.

Low temperature calorimetry is an experimental method of specific-heat measurement of condensed matters, and the specific heat is one of the most important and fundamental thermodynamic properties. There are mainly four methods of specific heat measurement, including adiabatic, relaxation, AC and continuing heating calorimetry. The adiabatic calorimetry is the most accurate and reliable in the specific heat measurement, since it is a static method that the sample can reach a thermal equilibrium during the measurement. However, there is no commercial adiabatic calorimeter yet because of complicated instrumentation, time consuming experimental procedures, and large sample amount requirements. The other three are dynamic specific heat measurement method, in which the sample is measured in a heating manner, and consequently a good thermal conductivity is required for a sample to obtain a reliable measurement. The specific heat is a bulk property of substance, and it can provide an average measure of the thermal properties of a sample. It is well known that the condensed states of matters are mainly controlled by the molecular motions, intermolecular interactions, and interplay among molecular structures. The physical property reflected in a material may be closely related to the energy changes in these three factors, which can be directly observed in a specific heat curve. Therefore, specific-heat measurements have been used not only to obtain entropy, enthalpy and Gibbs free energy, but also to investigate and understand lattice vibrations, metals, superconductivity, electronic and nuclear magnetism, dilute magnetic systems and structural transitions.

Two eight-coordination containing square antiprism polyhedra, [Ln(Gly) 4 Im·(ClO 4 ) 4 ] n (Ln:Nd, Sm) were synthesized through the self-assembly of Ln 3+ (Ln:Nd, Sm) ions, glycine and imidazole in aqueous solution and characterized by X-ray single crystal diffraction. Both of the complexes crystallized in the C 2/ c space group. In the cluster, each Ln 3+ ions was eight-coordination by eight oxygen atoms of the glycine. The coordination sphere of each Ln 3+ ions could be described as a distorted square antiprism. Two central Ln 3+ ions were connected by four bridging carboxyl groups from four glycine molecules. The Ln–O bond distances were related to the coordination geometries of the ligands. The complexes had two special solid–solid phase transitions at 224 K and 248 K, which were interpreted as a freezing-in phenomenon of the reorientational motion of perchlorate ions ClO 4 − and the orientational order/disorder process of ClO 4 − ions. The decomposition mechanism of the complexes was deduced to be three stages from 300 to 700 K. The fluorescent excitation and emission spectra showed that the complexes had strong fluorescent property.

A complex of copper perchlorate coordinated with imidazole Cu(C3N2H4)4(ClO4)2 was synthesized and characterized by X-ray single-crystal diffraction. The complex is centrosymmetric in the monoclinic P2(1)/c space group. The low-temperature molar heat capacities and thermodynamic properties of the complex were studied with adiabatic calorimetry (AC). The thermodynamic functions [H T–H 298.15] and [S T–S 298.15] were derived in the temperature range from 80 to 370 K with temperature interval of 5 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric (TG) analysis and differential scanning calorimetry (DSC). The mechanism of the decomposition was deduced to be the breaking up the two Cl–O bonds of the Cl–O–Cu and the Cu–N bonds of the imidazole rings in succession.

The heat capacities of 6-chlorouracil and 5-chlorouracil isomers were measured using a Quantum Design physical properties measurement system (PPMS) based on a heat pulse relaxation method over the temperature range from (1.9 to 300) K, and the experimental data were fitted as a function of temperature using a series of theoretical and empirical models for the appropriate temperature ranges. The results of these fits were used to calculate thermodynamic function values, C p , m 0 , △ 0 T S m o , and △ 0 T H m o from T = (0.5 to 300) K. The standard molar heat capacities, entropies and enthalpies of 6-chlorouracil and 5-chlorouracil at 298.15 K and 0.1 MPa were determined to be C p , m o = (136.94 ± 1.37) J K −1 mol −1 and (137.95 ± 1.38) J K −1 mol −1 , S m o = (156.87 ± 1.57) J K −1 mol −1 and (154.97 ± 1.55) J K −1 mol −1 and H m o = (23.01 ± 0.23) kJ mol −1 and (23.07 ± 0.23) kJ mol −1 , respectively.

A hydrous complex of erbium coordinated with glycine sodium perchloric acid, Er2(μ 2-Gly)6(H2O)4·Na2(ClO4)8(H2O)2·4H2O (Gly = glycine), was synthesized firstly and characterized by X-ray single-crystal diffraction. The complex crystallizes centrosymmetrically in the triclinic P-1 space group [a = 9.2959 (5), b = 12.1756 (7) A, c = 13.9928 (7) A, V = 1367.67 (13) A3, Z = 1]. The low-temperature molar heat capacities and thermodynamic properties of the complex were studied with adiabatic calorimetry. The thermodynamic functions, [H T–H 298.15] and [S T–S 298.15], were derived in the temperature range from 80 to 370 K with a temperature interval of 5 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric analysis and differential scanning calorimetry.

The heat capacities of three difluoromethyleneoxy liquid crystalline compounds (n-BB(F)B(F,F)XB(F,F)-F; n = 3, 4, 5) were measured using a quantum design physical properties measurement system (PPMS) based on a heat-pulse relaxation method in the temperature range from 1.9 to 300 K. The experimental results showed that the heat capacities of these three compounds increased with the temperature increment and none of the thermal anomalies were observed in the entire temperature region; and also the heat capacity values of n-BB(F)B(F,F)XB(F,F)-F (n = 3, 5) are larger than those of 4-BB(F)B(F,F)XB(F,F)-F due to the odd–even carbon effect below 21 K. The standard molar entropies at 298.15 K and 0.1 MPa were determined to be (631.14 ± 6.31), (650.21 ± 6.50), and (697.49 ± 6.97) J K−1 mol−1 for n-BB(F)B(F,F)XB(F,F)-F (n = 3, 4, 5), respectively.

The heat capacities of D-galactose and galactitol were measured on a quantum design physical property measurement system(PPMS) over a temperature range of 1.9―300 K, and the experimental data were fitted to a function of T using a series of theoretical and empirical models in appropriate temperature ranges. The fit results were used to calculate thermodynamic function values, C p,m θ , Δ 0 S m θ , and Δ 0 H m θ from 0 K to 300 K. The standard molar heat capacity, entropy and enthalpy values of D-galactose and galactitol at 298.15 K and 0.1 MPa were determined to be C p,m θ =(227.96±2.28) and (239.50±2.40) J·K−1·mol−1, S m θ = (211.22±2.11) and (230.82±2.30) J·K−1·mol−1 and H m θ = (33.95±0.34) and (36.57± 0.37) kJ/mol, respectively.

A heptanuclear trigonal prismatic polyhedron, [EuCu6(μ-OH)3(Gly)6Im6](ClO4)6·3H2O, was synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. The complex crystallize is the rhombohedral R3 space group (a = b = 15.8673 A, c = 23.4038 A, V = 5103.0(6) A3, Z = 3). In the clusters, Eu3+ ions are situated in the center of a prism formed by six copper atoms and coordinate to nine oxygen atoms with a tricapped trigonal prismatic coordination polyhedron. Six glycinato ligands and six imidazole terminal ligands (each coordinates to one Cu2+) were used in the construction of the cluster. The low-temperature molar heat capacity, C p,m, and thermodynamic properties of the complex were studied with an adiabatic calorimeter from 80 to 370 K. The thermodynamic functions [H T–H 298.15] and [S T–S 298.15] were derived in the temperature range from 80 to 370 K with a temperature interval of 5 K. The thermal properties of the complex from 300 to 800 K were studied by DSC and TG in nitrogen atmosphere.

A printed microstrip-fed four-port ultra-wideband (UWB) MIMO antenna is proposed. Four UWB antenna units are placed perpendicular to each other. Cross structure resonator is loaded on the back of the antenna to achieve high isolation. The UWB frequency is created by the rectangular patch with slots between the feedline and the patch on the front of the antenna. The overall volume of the antenna is 36.5×36.5×1.6mm3. The correlation coefficients of the antenna are less than 0.05 in the working frequency band. The isolation degree of each port is less than -15dB.The S parameters and the radiation patterns are measured and they are consistent with the simulation. The antenna can be applied to the UWB MIMO system.

Micro electroforming technology is widely used in fabrication of multilayer or moveable metal micro devices. The fabrication of these devices is usually suffered from high internal stress in micro-electroformed layers which seriously restricts the application and development of micro electroforming technology. Therefore, to control the internal stress is very important for improving the quality and performance of micro-electroformed layer. However, published studies on internal stress in the electroforming layer were mostly based on additive-free solution. According to additive solution, the effect of ultrasonic and current density on compressive stress occurring in the electroforming layer is investigated in this paper. The results indicate that the compressive stress keeps increasing with current density within range from 0.2 to 2 A/dm2. Meanwhile, the compressive stress in ultrasonic solution decreases by 73.4 MPa averagely comparing to that in ultrasonic-free solution, and the compressive stress also keeps decreasing with the ultrasonic power which gets the lowest value at 200W. Moreover, the mechanisms of additive-induced compressive stress and ultrasonic relieving compressive stress are discussed. This research work will complement the ultrasonic-stress reduction theory and may contribute to the development of micro electroforming technology.

Neodymium complex with glycine, Nd(Gly)2Cl3·3H2O, was synthesized and characterized by IR spectra. The thermal stability of the complex was tested through TG and DTG and a possible mechanism of thermal decomposition was proposed. The heat capacities of the complex were measured by using an automated adiabatic calorimeter over the temperature range from T = (80 to 380) K, the thermodynamic functions, [HT − H298.15] and [ST − S298.15], were calculated based on the heat capacity measurements. Two (solid + solid) phase transitions in the ranges of T = (170 to 247) K were observed with the peak temperatures of 184.896 K and 231.217, respectively. The standard molar enthalpy of formation of [Nd(Gly)2Cl3·3H2O] was determined to be (−3081.3 ± 1.1) kJ · mol−1 in terms of an isoperibol solution-reaction calorimeter.

Poly(p-aminobenzene sulfonic acid)-modified graphite electrode [poly(p-ABSA)/GE] was prepared via a straightforward one-step electropolymerization and was employed to investigate the electrochemical behavior of o-nitrophenol (o-NP), m-nitrophenol (m-NP) and p-nitrophenol (p-NP), for the purpose of realizing the simultaneous determination of nitrophenol isomers. Semi-derivative voltammetry (SDV) was adopted to enhance the resolution and sensitivity. Compared with the bare GE, poly(p-ABSA)/GE exhibited excellent electrocatalytic activity towards the oxidation process of the intermediate products of nitrophenol isomers. Thus, o-, m- and p-NP can be clearly identified and successfully separated at 0.119 V, −0.125 V and 0.027 V (vs. saturated calomel electrode). Under the optimized experimental conditions, the linear ranges of the calibration curves were 3∼800 μmol L −1 for o-NP, and 3∼700 μmol L −1 for both m-NP and p-NP. In addition, the low detection limits for o-, m- and p-NP were 0.28, 0.5 and 0.3 μmol L −1 , respectively (S/N = 3). The proposed method is novel and has many advantages such as simple, sensitive, selective, reproducible and cost-effective. Therefore, it can be considered a promising sensing platform for direct simultaneous determination of nitrophenol isomers in water samples.

Two heptanuclear trigonal prismatic polyhedra, [EuCu6(-OH)(3)(Gly)(6)Im(6)](ClO4)(6)3H(2)O and [SmCu6(-OH)(3)(Gly)(6)Im(6)](ClO4)(6)3H(2)O were synthesized through self-assembly of Eu3+(Sm3+), Cu2+, glycine, and imidazole in aqueous solution and characterized by X-ray single crystal diffraction. Both complexes crystallize in the rhombohedral R3 space group (a=b=15.8673 angstrom, c=23.4038 angstrom, V=5103.0(6)angstrom(3), Z=3) and (a=b=15.8749 angstrom, c=23.455 angstrom, V=5119.1(8)angstrom(3), Z=3). In the clusters, Sm3+ and Eu3+ ions are situated in the center of a prism formed by six copper ions and coordinate to nine oxygens with a tricapped trigonal prismatic coordination polyhedron. Six glycinato ligands and six imidazole terminal ligands (each coordinates to one Cu2+) construct the cluster. The fluorescent excitation and emission spectra showed that the complexes have strong ligand-based fluorescence.

The decomposition kinetics of the pure polyaniline (PANI), PANI/CeO2 composites, and PANI/Dy2O3 composites were investigated using thermogravimetry (TG) technique under air atmosphere. Two isoconversional methods and multiple linear regression method were used for the evaluation of kinetic parameters from the TG data of different heating rates. The estimation of activation energy values shows that the addition of CeO2 significantly enhances the thermal stability of PANI matrix, while the presence of Dy2O3 slightly reduces the thermal stability of the final composites. The kinetic analysis results show that the kinetic model for the decomposition process for PANI is D3 and for the two kinds of composites is F1–D1.

This paper reviewed and discussed some key issues of structural health monitoring (SHM) of long-span bridges. Firstly, the current situation of the application of structural health monitoring technique to long-span bridges was summarized in detail. Secondly, starting from the purpose of ensuring the safety of operational bridges, the composition characteristics and functional requirements of structural health monitoring system of long-span bridges were discussed, which include the global design principles of health monitoring system and the design approaches for each subsystem. Finally, some challenges of the technique of SHM were proposed including structural force analysis, the principles of optimized distribution of sensors and the assessment methods of structural damages of bridges etc,.

Low-temperature heat capacities of butyl 4-hydroxybenzoate have been measured by a high precision automated adiabatic calorimeter over the temperature range from 79 to 399 K. The melting temperature, the molar enthalpy and entropy of the phase transition were determined to be (342.227 ± 0.054) K, (26.122 ± 0.192) kJmol-1and (76.33 ± 0.55) JK-1mol-1.The thermodynamic functions (HT-H298.15K) and (ST-S298.15K) were calculated in the range from 80 to 400 K with the interval of 5 K. The constant-volume energy and standard molar enthalpy of combustion have been determined,cU (C11H14O3,s) =-(5760.30 ± 2.70) kJmol-1andcHm0(C11H14O3, s) =-(5765.26 ± 2.70) kJmol-1, by means of a precision oxygen-bomb combustion calorimeter atT= 298.15 K. The standard molar enthalpy of formation has been derived,fHm0(C11H14O3, s) =-( 564.16 ± 4.41) kJmol-1, from the standard molar enthalpy of combustion in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle.

Molar heat capacities (Cp,m) of the ionic liquids (ILs) N-alkylpyridinium hexafluorophosphate [Cnpy][PF6] (n = 2, 3, 5) were measured with a high-precision automated adiabatic calorimeter (AC). The melting temperatures were determined. The molar enthalpy and entropy of phase transition were calculated according to the data obtained of the molar heat capacities by the empirical equation. The polynomial equations of molar heat capacity as a function of the temperature were fitted before and after the phase transition for each IL compounds. The thermodynamic functions (HT − H298.15) and (ST − S298.15) were derived from the molar heat capacity values over the temperature range from (80 to 400) K with an interval of 5 K.

The complex of pyridine 2,6-dicarboxylate with Ba2+ ion Ba(HDPC)(2)center dot 2H(2)O(s) was synthesized. X-ray crystallography was applied to characterize the crystal structure of the complex. Low-temperature heat capacities of the complex were measured with an automated adiabatic calorimeter in the temperature range from 78 to 360 K A polynomial equation of experimental molar heat capacities as a function of the temperature was obtained by the least-squares method. The smoothed heat capacities and thermodynamic functions of the complex were calculated based on the fitted polynomial equation. In addition, the standard molar enthalpies of dissolution for the reactants and products of the synthesis reaction in a selected solvent were measured by an isoperibol solution-reaction calorimeter, and the standard molar enthalpy of formation of the title complex was calculated as - (2993.0 +/- 3.0) kJ mol(-1) by the Hess thermochemical cycle. Furthermore, the reliability of the designed thermochemical cycle was verified by UV-vis spectroscopy. (C) 2013 Elsevier B.V. All rights reserved.

Crystalline bis-(n-dodecylammonium) tetrachlorocuprate (n-C12H25NH3)(2)CuCl4(s) and bis-(n-dodecylammonium) tetrachlorocadmate (n-C12H25NH3)(2)CdCl4(s) were synthesized. Chemical analysis, elemental analysis and X-ray crystallography were applied to characterise the compositions and crystal structures of the two complexes. In accordance with Hess' law, two thermochemical cycles were designed, and the enthalpy changes of the reactions of n-dodecylammonium hydrochloride with CuCl2 center dot 2H(2)O(s) and CdCl2-center dot 2.5H(2)O(s) were determined as Delta H-r(m)degrees(,1) = (32.86 +/- 0.40) kJ . mol(-1) and Delta H-r(m)degrees(,2) = -(5.28 +/- 0.38) kJ . mol(-1) by an isoperibol solution-reaction calorimeter, respectively. Eventually, the standard molar enthalpies of formation of the title compounds were derived to be Delta H-f(m)degrees [(n-C12H25NH3)(2)CuCl4, s] = -(1630.4 +/- 8.0) kJ . mol(-1) and Delta H-f(m)degrees [(n-C12H25NH3)(2)CdCl4, s] = -(1836.2 +/- 8.0) kJ . mol(-1), respectively. (c) 2013 Elsevier Ltd. All rights reserved.

In order to describe the influence of pr6o11 on thermal and electrochemical performance of polyaniline (pani), pani/pr6o11 composites were synthesized by in situ polymerization in the presence of sulfosalicylic acid (as dopant). the composites obtained was characterized by scanning electron microscope, fourier transform infrared spectra, and x-ray diffraction. the thermal stability of the composites was investigated by thermogravimetry and derivative thermogravimetry. finally, the comparative analysis on the electrochemical properties of pani/pr6o11 composites electrodes, such as cyclic voltammetry, electrochemical impedance spectroscopy, and constant current charge-discharge test, was conducted under similar conditions. scanning electron microscope, infrared, and x-ray diffraction results show that interaction exists between pani and pr6o11, and the composites are more crystalline than pure pani. thermogravimetry and derivative thermogravimetry analyses indicate that pani/pr6o11 composites and pure pani have similar thermal stability. moreover, the studies regarded to capacitive properties show that the electrochemical performance of the composites is improved greatly when pr6o11 is added in small amount. however, with increasing the amount of pr6o11, the electrochemical performance of the composites become worse, which indicates a large amount of pr6o11 has a negative effect on the capacitance. these results suggest that pani is still in the conductive form after inserting the pr6o11, and the capacitance performance of pani can be improved only by a low percentage of pr6o11. copyright (c) 2013 john wiley & sons, ltd.

The elastic structure of the anchor-fixed monolayer cable net generates elastic displacement under pre-tension, so the designed tension of the cable can be consistent after repeated test and it is difficult to control in later construction. For this case, we get causes for elastic displacement based on comprehensive analysis, simulate and analyze it by using displacement compensation tension method to compute all initial tensions once time and guarantee consistent designed tensions after elastic distortion of a cable. We make the construction sequence and record the force and tension of each cable after it is strained in place based on computed initial pre-tension in order to monitor if the distortion is reasonable in tension and guarantee in-place tension in construction once time without repetition.

Structural finite element model (FEM) updating in dynamics usually deemed the measured modal parameters as the goal. By modifying the theoretical FEM, the updated modal parameters obtained by the analytical FEM would finally tend to the testing results. But the own complexity of the civil structure leads the optimization problem of FEM updating to be super-size and high non-linear performance. Moreover, the uncertainty and nonuniformity of the structures, material and the environment effect cause the uncertainty of the updating parameters, even the optimization objective function of FEM updating. These features has brought greater difficulty to the model updating in civil engineering structure, especially for the application field. Therefore, in this paper several kinds of methods for FEM updating would be introduced with the comparison of their advantages, disadvantages and the range of application. At the end of this paper, the problems remained to be solved in FEM updating of civil structures are to be presented.