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A simple mixing of a hot- and cold-water stream at a T-junction was investigated. The main objective was to use mass and energy balance equations to predict mass low rates and the temperature of the mixed stream after the T-junction, and then compare these with the measured values. Furthermore, the thermocouple location after the T-junction and the reproducibility of the data were also investigated. (Contains 3 tables and 3 figures.)

The crop leaf color is tightly connected with its meteorological environment. Color gradation skewness-distribution (CGSD) parameters can describe the information of leaf color more accurately, systematically, and comprehensively from five dimensions. We took photographs of pepper growing in the greenhouse at a fixed time every day and observed the meteorological factors. The results showed that the CGSD parameters were significantly correlated with meteorological factors, especially with the accumulated temperature, which showed the strongest correlation. Since the relationship between canopy leaf color and accumulated temperature is nonlinear, the piecewise inversion models were constructed by taking the stationary point of the high-order response model of Gskewness to accumulated temperature as the point of demarcation. The rate of outliers had decreased by 57.72%; moreover, the overall inversion accuracy had increased by 3.31% compared with the linear model directly constructed by the stepwise regression. It was observed that the pepper in the greenhouse had a different response to the same meteorological environmental stimulus before and after the stationary point. This study will provide a new method for constructing crop growth models in future research. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of Yangxin Shengmai (Heart-nourishing Pulse-engendering) Granule (YXSM Granule) on rats with coronary heart disease complicated with anxiety and depression through BDNF/TrKB pathway. Methods 124 SD rats were randomly divided into the blank group (n =14) and the model group (n =110). Except for the blank group, the depression model was established with Chronic Unpredictable Mild Stress (CUMS) for 28 days. On the 15th day, the myocardial infarction reperfusion model was established by ligating the left anterior descending coronary artery. Among the rat models, 14 rats were operated but not ligated, and they were set as the sham operation group; the others were randomly divided into model group and low-, medium- and high-dose (2.1,4.2,8.4 g/kg) YXSM Granule groups and 0.29 g/ kg Compound Danshen tablet + Fluoxetine (CDST+Flu) group. After intragastric administration for 2 weeks, the rats in each group undergone behavioral tests. The myocardial injury, left ventricle diameter (LVD) and left ventricular wall thickness (LVWT) were observed by HE staining, the protein expression levels of BDNF, TrKB and CD34 in myocardial tissue were detected by immunohistochemistry, and the protein expression levels of BDNF, TrKB and p-TrKB in hippocampus were detected by Western blotting. Results Compared with the sham group, the frequency of entering the central area of the open field and the total time spent and total distance travelled in the movement track in the model group were significantly reduced (P < 0.01), and the frequency and proportion of time spent in the open arm of the elevated cross maze were significantly reduced. Compared with the model group, the frequency of entering the central area of the open field and the total time spent and distance travelled in the movement track in all YXSM Granule groups and CDST+ Flu group were significantly increased (P<0.01), and the frequency and proportion of time spent in the open arm of the elevated cross maze were significantly increased, but with no significant difference. Compared with the sham operation group, in the model group, the degree of myocardial injury and LVD were significantly increased (P<0. 01), the LVWT and the protein expression levels of BDNF, TrKB and CD34 in myocardial tissue and BDNF and p-trkb/TrKB in hippocampus decreased significantly (P<0.05, P<0.01). Compared with the model group, the degree of myocardial injury was significantly improved, the LVD was significantly reduced (P<0.01), the LVWT and the protein expression levels of BDNF, TrKB and CD34 in myocardial tissue and BDNF and p-TrKB/ TrKB in hippocampus were significantly increased (P<0.05, P<0.01) in all the other groups. Conclusion YXSM Granule seems to improve the cardiac function and alleviate depressive symptoms in rats with coronary heart disease with anxiety and depression, which may play a cardioprotective and antidepressant role by activating BDNF/TrKB signal pathway. [ABSTRACT FROM AUTHOR]

We developed a tip-enhanced Raman spectrometer (TERS) with reflection mode. The instrument, with a scanning shear-force microscope (ShFM) and a side-illumination Raman spectroscope, can overcome the diffraction limit and has high sensitivity. A chemical method to fabricate optical fiber probes with Ag coating is proposed. The local electromagnetic responses of the silver-coated optical fiber probe are numerically analyzed by the finite-difference time-domain method, and the excitation wavelength is optimized to resonate with the localized surface plasmons (LSP) of the probe tip. The instrument is applied to investigate a single multiwall carbon nanotube. The experiment results indicate that our TERS instrument has a spatial resolution better than 70 nm, and the enhancement factor is about 5 x [10.sup.3]. OCIS codes: 180.4243, 120.6200, 300.6450.

A method for rapid quantitative analysis of the content and distribution of short chain branching (SCB) for α-olefin/ethylene copolymers based on thermally fractionated DSC is presented. Eight commercial polyethylenes, four made with conventional Ziegler-Natta catalysts and four made with metallocene catalysts, were analyzed by differential scanning calorimetry (DSC), after having been thermally segregated by successive nucleation annealing (SNA). The polyethylenes were also analyzed by temperature rising elution fractionation (TREF) and carbon-13 nuclear magnetic resonance ([.sup.13]C-NMR). The SNA-DSC procedure segregates polyethylenes according to methylene sequence lengths (MSL). The relationship between DSC melting temperature and SCB content was obtained by calibration with linear hydrocarbons; TREF results were not used in the SNA-DSC calibration. Deconvolution of the SNA-DSC endotherms yielded estimates of the average SCB contents and SCB distributions. The SCB contents obtained from the SNA-DSC for linear low density polyethylenes agreed very well with the SCB contents obtained by [.sup.13]C-NMR and TREF, and the SCB distributions measured by SNA-DSC were very similar to those obtained by TREF. The SCB contents obtained by SNA-DSC for ultra-low density polyethylenes, made with metallocene catalysts, were about 20% lower than the values obtained by [.sup.13]C-NMR; the values obtained by TREF were even lower., INTRODUCTION Polyethylenes synthesized by the copolymerization of ethylene and α-olefins with either Ziegler-Natta or metallocene catalysts are major commodity polymers worldwide. The properties, and hence the end uses, of commercial [...]

Coalescence and flocculation are two challenges for the stability and efficacy of pesticide suspension concentrate (SC) during the production and storage. To improve the stability of 25% pymetrozine SC, three comb‐like poly(styrene‐co‐acrylic acid‐co‐polyethylene glycol methyl ether maleate) (SA‐M) with different length side chains were synthesized by free radical polymerization and characterized by Fourier transform infrared spectroscopy and H‐nuclear magnetic resonance. Surface‐active parameters, including critical aggregation concentration (critical micelle concentration), saturation surface excess concentration (Γmax), minimum area per molecule (Amin), and standard Gibbs free energy ΔGm0 values were obtained from surface tension measurement. It shows that the surface‐active property of SA‐M decreased with the side chain length. Besides, 25% pymetrozine SC prepared using SA‐M as dispersant had low zeta potential and low viscosity but high dispersibility and thermal storage stability. It is speculated that the formation of hydrogen bonds between nonionic branches and pymetrozine molecule at the expense of interruption of intermolecular hydrogen bonding between pymetrozine and water molecule, plays a key role in the stability mechanism. [ABSTRACT FROM AUTHOR]

Here, we report a simple but effective nose/tongue-mimic sensor array based on HAuCl4/3,3′,5,5′-tetramethylbenzidine (TMB) for colorimetric discrimination and determination of antioxidants. Two concentrations of HAuCl4 were employed as receptor units to construct the colorimetric sensor array. The sensing strategy is based on the fact that HAuCl4 with different concentrations (0.08 and 0.03 mM) could oxidize TMB to oxidized TMB (oxTMB), resulting in a blue and green color solution, respectively, corresponding to an absorption peak centered at 440 nm and 657 nm. However, the presence of different antioxidants could cause the reduction in HAuCl4, leading to the fading of the blue and green color and the decrease in the absorbance at 440 nm and 657 nm to varying degrees. Based on the above phenomena, by taking advantage of linear discriminant analysis (LDA), five antioxidants (i.e. ascorbic acid (AA), melatonin (MT), uric acid (UA), tannic acid (TCA), and glycine (Gly)) at five concentrations (200, 120, 60, 20, and 1 nM) were successfully discriminated both in buffer and serum. More importantly, this approach is simple, fast, and without the use of any nanomaterials. [ABSTRACT FROM AUTHOR]