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Gold nanorods are of great significance in biomedical and sensing applications due to their local surface plasmon resonance absorption. The silver-mediated seeding method was used to prepare gold nanorods, the longitudinal local surface plasmon resonance (LSPR) absorption of the prepared gold nanorods was monitored, and the growth kinetics of the gold nanorods were discussed. The results show that the growth process of gold nanorods is characterized by a first-order reaction, and its activation energy is about 54.4 kJ/mol. This experimental conclusion provides a good theoretical guide for the preparation of gold nanorods during application research.

Fraxinellone is an important botanical lactone compound and has been demonstrated to have insecticidal activity. To provide theoretical support to the assessment on the safety of utilizing fraxinellone as a natural insecticidal agent, the interactions between fraxinellone and armyworm DNA, salmon sperm DNA and calf thymus DNA were investigated using UV–Vis absorption spectroscopy, isothermal titration calorimetry, and molecular docking. Results showed that there were two types of combinations between fraxinellone and three kinds of DNA. Type I combination had an equilibrium constant of combination (Ka1) of about 105 and binding sites (n1) of 0.40–0.70, while type II combination had an equilibrium constant of combination (Ka2) of 103 and binding sites (n2) of 1.35–3.15. Results of molecular docking showed that there were non-classical embedding type interactions between fraxinellone and three kinds of DNA, with the reaction taking place in small groove areas of the DNA structure, resulting in relatively weak interactive forces.

Mesoporous titanium dioxide with a “lotus root”-like structure was synthesized for the first time using an improved template-free method. The structure has a BET (Brunauer Emmett Teller) surface area of 688.11 m2/g, a pore volume of 0.743 cm3/g, and a pore size of 3.59 nm. Aconitine, a botanical insecticide, could be loaded onto the mesoporous titanium dioxide via simply soaking the structure and had a maximum loading of 17.6%. UV spectroscopy was utilized to explore the drug release behaviors, and the results showed that aconitine-loaded mesoporous titanium dioxide particles UV irradiated could successfully release aconitine with a release rate of 46.24%, which was significantly higher than the samples lacking UV irradiation (36.80%). Meanwhile, the release rate of aconitine (48.94%) for pH 5.5 was significantly higher than that for pH 7.0 (42.09%). The results of microcalorimetry revealed that both the enthalpy change (ΔH) and entropy change (ΔS) were negative (ΔH

MXenes have drawn considerable attention in both academia and industry due to their attractive properties, such as a combination of metallic conductivity and surface hydrophilicity. However, to the best of our knowledge, the potential use of MXenes in non-volatile resistive random access memories (RRAMs) has rarely been reported. In this paper, we first demonstrated a RRAM device with MXene (Ti3C2) as the active component. The Ti3C2-based RRAM exhibited typical bipolar switching behavior, long retention characteristics, low SET voltage, good mechanical stability and excellent reliability. By adjusting different compliance currents in the SET process, multi-state information storage was achieved. The charge trapping assisting hopping process is considered to be the main mechanism of resistive switching for this fabricated Ti3C2-based RRAM, which was verified by conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). Moreover, this flexible Ti3C2-based RRAM, with good mechanical stability and long retention properties, was successfully fabricated on a plastic substrate. Ti3C2-based RRAMs may open the door to additional applications and functionalities, with high potential for application in flexible electronics.

In this paper, we selected quercetin and aromatic amino acids (tryptophan, tyrosine, phenylalanine) as the research objects to investigate the change rules in the reaction process. The thermodynamic functions (Ka, ΔG, and ΔS) of the interactions between quercetin and aromatic amino acids (tryptophan, tyrosine, phenylalanine) were measured by isothermal titration calorimetry. The values of binding constant (Ka) reached maximum at 25°C; the entropies and Gibbs free energies were both negative at different temperatures. The kinetic parameters of quercetin and amino acids in the interaction process was determined by microcalorimetry. The results inferred that the driving force of the reaction was hydrogen bond or van der Waals force.

MXenes have drawn considerable attention in both academia and industry due to their attractive properties, such as a combination of metallic conductivity and surface hydrophilicity. However, to the best of our knowledge, the potential use of MXenes in non-volatile resistive random access memories (RRAMs) has rarely been reported. In this paper, we first demonstrated a RRAM device with MXene (Ti3C2) as the active component. The Ti3C2-based RRAM exhibited typical bipolar switching behavior, long retention characteristics, low SET voltage, good mechanical stability and excellent reliability. By adjusting different compliance currents in the SET process, multi-state information storage was achieved. The charge trapping assisting hopping process is considered to be the main mechanism of resistive switching for this fabricated Ti3C2-based RRAM, which was verified by conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). Moreover, this flexible Ti3C2-based RRAM, with good mechanical stability and long retention properties, was successfully fabricated on a plastic substrate. Ti3C2-based RRAMs may open the door to additional applications and functionalities, with high potential for application in flexible electronics.

The dissolution behavior of cis-diammineglycolatoplatinum (nedaplatin) in saline, water and glucose were studied by a microcalorimetric method. The integral heats and differential heats of the dissolution were measured to establish the equation for the solute and the heats. The corresponding half-life, kinetic and thermodynamic properties of the nedaplatin solutions were determined. The results show that hydrogen bonds could be generated and the dissolution entropy of nedaplatin in different solvents is negative during the dissolution process, so as to enhance the drug stability, but there is an obvious difference in stability in different solvents.

It is desirable to imitate synaptic functionality to break through the memory wall in traditional von Neumann architecture. Modulating heterosynaptic plasticity between pre- and postneurons by another modulatory interneuron ensures the computing system to display more complicated functions. Optoelectronic devices facilitate the inspiration for high-performance artificial heterosynaptic systems. Nevertheless, the utilization of near-infrared (NIR) irradiation to act as a modulatory terminal for heterosynaptic plasticity emulation has not yet been realized. Here, an NIR resistive random access memory (RRAM) is reported, based on quasiplane MoSe

To investigate the diagnostic value of urinary neutrophil gelatin enzyme-related lipid delivery protein (NGAL) and kidney injury molecule-1 (KIM-1) in the acute kidney injury (AKI) after cardiopulmonary bypass (CPB) operation in children with non-cyanotic congenital heart disease (CHD).A retrospective analysis was conducted. 200 CPB undergoing cardiac surgery in children with non-cyanotic CHD admitted to Tianjin Children's Hospital from June 2015 to May 2017 were enrolled. All patients were divided into AKI group and non-AKI group within 48 hours after operation, and the two groups matched with age, sex, weight, basic complications, operation time and other factors. The differences in serum creatinine (SCr), urinary NGAL and KIM-1 [corrected for urinary creatinine (UCr)] between the two groups before and after operation were compared. The early diagnosis value of urinary NGAL and KIM-1 on AKI was analyzed by the receiver operating characteristic curve (ROC).There were 32 patients with different degrees of AKI 48 hours post operation, and the incidence was 16.0%; 60 cases were enrolled in non-AKI group. Compared with non-AKI group, urinary NGAL at 2 hours after operation, urine KIM-1 at 4 hours after operation, and SCr at 10 hours after operation in AKI group were significantly increased, which decreased gradually after reaching peak at 6, 8, 24 hours respectively. It was shown by ROC curve analysis that the area under ROC curve (AUC) and 95% confidence interval (95%CI) of postoperative 2-hour urine NGAL, 4-hour urine KIM-1 and 10-hour SCr for diagnosis of AKI were 0.940 (95%CI = 0.890-0.990), 0.939 (95%CI = 0.891-0.986) and 0.959 (95%CI = 0.916-1.000) respectively. When the cut-off value of postoperative 2-hour urine NGAL was 588.0 μg/g, the sensitivity was 87.5%, the specificity was 95.0%, the accuracy was 93.5%; when the cut-off value of postoperative 4-hour urine KIM-1 was 9.55 ng/mg, the sensitivity was 87.5%, the specificity was 91.7%, the accuracy was 90.2%; and when the cut-off value of postoperative 10-hour SCr was 61.90 μmol/L, the sensitivity was 90.6%, the specificity was 95.0%, and the accuracy was 95.7%.Urine NGAL and KIM-1 can be used as biomarkers for early diagnosis of AKI after CPB for the non-cyanotic CHD in children.

The dissolution process of penicillin in normal saline and isotonic glucose solution was reported using a microcalorimeter. Both the integral and differential heats of solution were measured. The quantitative relationships between the amount of heat released and the quantity of dissolved penicillin were established. Meanwhile, the kinetics and the half-life of the dissolution processes as well as the enthalpy of solution, the entropy of dissolution, and the free energy of dissolution were determined. The results showed that a change of the solvent from normal saline to isotonic glucose solution had little effect on the half-life of penicillin in the dissolution process, and there was no significant difference between the stabilities of penicillin in isotonic glucose solution and normal saline. Moreover, the dissolution process of penicillin in isotonic glucose solution followed the first-order kinetics. These results could provide a theoretical basis for the clinical applications of penicillin.

In this paper, the enthalpies of dissolution of oxysophocarpine in water were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure, showing that the dissolution process was an endothermic and exothermic oscillation behavior. A series of thermodynamics functions and the half-life were obtained by thermodynamic and kinetic methods. The results show that this work not only provide a simple method for the determination of the half-life for a drug but also offer a theoretical reference for the clinical application of resveratrol.

Variations of H+, Mn2+, and \({{\rm BrO}_3^-}\) during chemical oscillating reactions involving amino acids were investigated using H2SO4–\({{\rm BrO}_3^{-}}\) –Mn2+–acetone as an oscillator, and the thermodynamic functions (ΔS, ΔH, and ΔG) were calculated. The results indicated that the oscillating reaction is a process from disorder to order. In the oscillating system, the heat provided by the environment is used to increase the internal energy and entropy. When external positive entropy flow could make the system reach negative entropy flow, the system starts to oscillate and to maintain oscillations by a stable entropy.

In this article, the enthalpies of dissolution of resveratrol in dimethyl sulfoxide (DMSO) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure. The differential enthalpy (Δdif H m) and molar enthalpy (Δsol H m) of dissolution of resveratrol in DMSO were determined, and the relationship between heat and the amount of solute was also established. Based on the thermodynamic and kinetic knowledge, the corresponding kinetic equation, half-life, Δsol H m, Δsol S m, Δsol G m, the relative partial molar enthalpy (Δsol H m(partial)) and the relative apparent molar enthalpy (Δsol H m(app)) of the dissolution process were obtained. The results showed that this study not only provided a simple method for the determination of the half-life for a drug, but also offered a theoretical reference for the clinical application of resveratrol.

Silver nano-crystals in the forms of nanowires and triangular nanoplates were successfully synthesized through a polyol synthesis. The morphologies changed from nanowires to triangular nanoplates by adjusting the HNO3 concentration. The samples were systematically characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscropy, thermogravimetric analysis and UV–visible Spectra. Examination of nanoparticles at different stages of the reaction revealed that the circular nanoparticles, twinned seeds grew to become triangular nanoplates and nanowires respectively.

With the help of the kinetic parameters (the rate constant (kinkp) and the apparent activation energy (EinEp) of the oscillatory induction period and oscillation period) of the oscillating reaction using thirteen amino acids, leucine (Leu), threonine (Thr), arginine (Arg), lysine (Lys), histidine (His), alanine (Ala), glutamine (Glu), glycine (Gly), methionine (Met), cystine (Cys), tryptophan (Trp), serine (Ser) and tyrosine (Tyr), as organic substrates in amino acid-BrO3−-Mn2+-H2SO4-acetone system, then based on the Oregonator model and the thermodynamics theory on irreversible process, the thermodynamic function (ΔHin, ΔGin, ΔSin and ΔHp, ΔGp, ΔSp) of these oscillating system are studied. The results indicate the entropy ΔS of these oscillating reaction are negative, thereby it is proved that the oscillating reaction is a noequilibrium system with dissipation structure in agreement with the character of the oscillating reaction from disorder to order in irreversible thermodynamics. These are satisfactorily to explain the experimental phenomena.

A polyol reducing approach has been applied to synthesize silver nanoplates with an average thickness of 50 nm and edge length of 3 μm in the presence of poly (vinylpyrrolidone) (PVP) and HNO3. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscropy (TEM), and electron diffraction are used to characterize these silver nanoplates. Findings indicate that the nanoplates are single crystals and with their basal plane as (1 1 1) lattice plane. On the basis of the results from thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy, a crystal growth mechanism based on the rivalrous adsorption between PVP and CN− ions on the surface of silver nanoplates is supposed to explain the crystal anisotropic growth.

Laburnine’s dissolution behaviors in glucose and saline solution were studied by a micro-calorimetry method. The measured integral and differential heats of solution were utilized to build equations of the solute and the heat, so that dissolution thermodynamic equations and half-time periods, Δsol H m, Δsol G m, and Δsol S m were obtained. The results show that this study does not only provide a simple method for the determination of the half-life period for a drug but also offer a theoretical reference for the clinical application of laburnine.

In this paper, the enthalpies of dissolution of matrine in ethanol (EtOH) were measured using a RD496-2000 Calvet microcalorimeter at 309.65 K under atmospheric pressure. The differential enthalpy (Δdif H m) and molar enthalpy (Δsol H m) of dissolution of matrine in ethanol were determined. And the relationship between heat and the amount of solute was also established. Based on the thermodynamic and kinetic knowledge, the corresponding kinetic equation that described the dissolution process was determined to be $${\frac{{\rm d}\alpha}{{\rm d}t}=2.36\times 10^{-4}(1-\alpha )^{1.09}}$$ . Moreover, the half-life, t 1/2 = 48.89 min, Δsol H m = −12.40 kJ · mol−1, Δsol S m = −354.7 J · mol−1 · K−1, and Δ sol G m = 97.43 kJ · mol−1 of the dissolution process were also obtained. The results show that this work not only provides a simple method for the determination of the half-life for a drug but also offers a theoretical reference for the clinical application of matrine.

In this article, the enthalpy of dissolution for oxymatrine in 0.15 M citric acid solution is measured using a RD496-2000 Calvet Microcalorimeter at 36.5 °C under atmospheric pressure. The differential enthalpy (Δ dif H m) and molar enthalpy (Δ sol H m) were determined for oxymatrine dissolution in 0.15 M citric acid solution. On the basis of these experimental data and calculated results, the kinetic equation, half-life, Δ sol H m, Δ sol G m, and Δ sol S m of the dissolution process were also obtained.

The enthalpies of dissolution of oxymatrine in 0.9%NaCl solution were measured using a RD496-2000 Calvet Microcalorimeter at 309.65 K under atmospheric pressure. The differential enthalpy and molar enthalpy of oxymatrine dissolution in the 0.9%NaCl solution of were determined. The corresponding kinetic equation that described the dissolution process was elucidated. Moreover, the half-life, molar entropy, molar enthaply, and Gibbs free energy of the dissolution process were also obtained.

Photonic memories as an emerging optoelectronic technology have attracted tremendous attention in the past few years due to their great potential to overcome the von Neumann bottleneck and to improve the performance of serial computers. Nowadays, the decryption technology for visible light is mature in photonic memories. Nevertheless, near-infrared (NIR) photonic memristors are less progressed. Herein, an NIR photonic memristor based on MoS2 -NaYF4 :Yb3+ , Er3+ upconversion nanoparticles (UCNPs) nanocomposites is designed. Under excitation by 980 nm NIR light, the UCNPs show emissions well overlapping with the absorption band of the MoS2 nanosheets. The heterostructure between the MoS2 and the UCNPs acting as excitons generation/separation centers remarkably improves the NIR-light-controlled memristor performance. Furthermore, in situ conductive atomic force microscopy is employed to elucidate the photo-modulated memristor mechanism. This work provides novel opportunities for NIR photonic memory that holds promise in future multifunctional robotics and electronic eyes.

Vertically aligned ZnO nanowires with high aspect ratio were prepared by chemical vapor deposition on Si substrate, which had been catalyzed by the polar plane in [0001] direction of ZnO nanorods prepared by the hydrothermal method. Morphology and structure characterizations showed that the as-grown nanowires had the single-crystal hexagonal wurtzite structure with a [0001] growth direction. Energy Dispersive X-ray (EDX) measurement indicated the as-grown ZnO nanowires had a good deal of oxygen vacancies owing to the high operation temperature. Temperature-dependent photoluminescence measurement revealed that the peak of near-band-edge emission shifted from 380 to 387 nm with the increase of temperature from 150 to 300 K. The high intensity of the green peak at 525 nm highlighted the potential application in visible light emitting diodes.

Pulsed laser photolysis/laser-induced fluorescence (LP-LIF) is utilized to measure rate constants for C2(a3Πu) reactions with NO, N2O, O2, H2 and NH3. Multiphoton dissociation of C2Cl4 at 266 nm is employed for the generation of C2(a3Πu) radicals. The C2(a3Πu) concentration is monitored by the fluorescence of the (0, 0) band of the (d3Πg↔a3Πu) transition at 516.5 nm. C2(a3Πu) removal rate constants for the reactions are determined as kNO = (5.46 ± 0.10) × 10−11 cm3 molecule−1 s−1, $$\begin{gathered} k_{NO} = (5.46 \pm 0.10) \times 10^{ - 11} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{N_2 0} = (1.63 \pm 0.20) \times 10^{ - 13} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{N_2 0} = (1.58 \pm 0.16) \times 10^{ - 11} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{0_2 } = (5.92 \pm 1.00) \times 10^{ - 14} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{H_2 } = < \hfill \\ \end{gathered} $$ .

This article described the synthesis and application of 6-chloro-8-fluoro-4-methylumbelliferone phosphate (CF-MUP) in analyzing acid phosphatase activity. Compared to the existing MUP, the new coumarin phosphate, CF-MUP, demonstrateed much higher sensitivity and was more robust for detecting the activity of acid phosphatase than the classic substrate 4-methylumbelliferone phosphate (MUP). The product of enzyme reaction, 6-chloro-8-fluoro-4-methylumbelliferone (CF-MU) possesses strong fluorescence at approximately 450 nm with low pKa (4.7), high fluorescence quantum yield and pH independence in the physiological pH range. This new fluorescence dye, CF-MU, is a convenient tool for assays with buffer pH between 4.5 and 8.

A new hasubanane-type alkaloid, named 8-demethoxyrunanine, was isolated from the rhizome of Sinomenium acutum. Its structure was determined by spectroscopic methods and X-ray diffraction analysis.

A new method is found in distinguishing Chinese medicinal herbs.Chemical oscillating technology was used to study discrimination of Chinese medicinal herbs.Chemical oscillating fingerprints of over 30 kinds of Chinese medicinal herbs were obtained.Chemical oscillating fingerprints can be used to distinguish Chinese medicinal herbs.

Trans-2,2',4,4'-tetramethyl-6,6'-dinitroazobenzene from the leaves of Aconitum sungpanense was reported as a new compound. The structure was determined by spectroscopic methods and X-ray diffraction analysis.

The oscillating behavior of thirteen amino acids [leucine (Leu), threonine (Thr), arginine (Arg), lysine (Lys), histidine (His), alanine (Ala), glutamine (Glu), glycine (Gly), methionine (Met), cystine (Cys), tryptophan (Trp), serine (Ser) and tyrosine (Tyr)] in amino acid-BrO - 3 -Mn2+-H2SO4-acetone system is studied by using a potentiometric determination. With the help of the oscillatory induction period and oscillation period obtained by the oscillating wave, and Arrhenius equation, the kinetic parameters [the apparent activation energy (E) and pre-exponential constant (A)] and rate constant (k) of the above-mentioned oscillating reaction are estimated.