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Electronic expansion valve (EEV) takes advantages of its fast response, wide working range and accurate control and is been widely used in CO2 heat pump and air-conditioning system while the CO2 mass flow characteristics is the most crucial parameter for EEV. Different from other refrigerants, at the inlet of EEV, CO2 maintains at supercritical state. In this study, the effects of inlet pressure, inlet temperature, outlet pressure, EEV flowing area and EEV geometries on CO2 mass flowing through EEVs have been investigated under a wide operation range for three different EEVs. Meanwhile, a new empirical correlation has been developed to predict the mass flow rate of CO2 flowing through EEVs based on the experimental data. The proposed dimensionless correlation shows a good agreement with the test data. Approximately 91.8% of the experimental data within a relative deviation of ±5% for all EEVs. The average deviation and standard deviation of the predictions are 0.36% and 1.93% respectively.

Although the weighted total least squares (WTLS) adjustment is a rigorous method for estimating parameters in errors-in-variables (EIV) models, its solution is unreliable if the design matrix and/or observations contain multiple outliers. Existing methods are not capable of fully eliminating the influence of multiple outliers on the parameters. First, we reformulate an EIV model as a correction model by taking the outliers of the design matrix and observations into account, and we introduce the concept of total outliers to simplify the problem of detecting multiple outliers in EIV models. Then, based on the effect of the outliers on the estimated posteriori variance, we develop a full search algorithm to form a location matrix that can describe the location of the total outliers. Next, we derive a set of formulae to numerically estimate the unknown model parameters and total outliers simultaneously. Finally, the results of three numerical experiments show that the proposed method can effectively eliminate the influence of the outliers and obtain reliable parameters.

A high gain, low thermal-induced wavefront distortion, laser diode-pumped Nd: YAG slab amplifier is demonstrated with its active media dimensions of 7 mm × 35 mm × 138.2 mm. Under the 200 Hz, 1440 W pulse pumping condition while no seed light to amplify, the thermal induced wavefront aberration of a He-Ne probe passing through the gain meUdium is 0.165 λ @633 nm (RMS). The amplifier shows stable aberration character with two major low-order terms, defocus and 0° astigmatism. The fluorescence distribution, stored energy, and small-signal gain of the amplifier are measured and have a good agreement with the calculated results. In the amplifier, the fluorescence is uniformly distributed and the maximum stored energy of 3.2 J can be achieved with a plane-concave cavity at 200 Hz pump repetition frequency. For a repetition frequency of 200 Hz, 25 μ J injection polarized seed-light and 1440 W pump power, the small signal gain reaches 9.45. The amplifier has been successfully employed in a 200 Hz, 5 J, MOPA system with 1.7 times diffraction limited output.

A diode-double-face-pumped Nd:YAG ceramic slab laser amplifier with uniform gain distribution and low depolarization loss was presented. Energy storage of 2.6 J was achieved at 1064 nm with a repetition rate of 200 Hz and a pulse width of 200 us from a 140 mm × 40 mm × 7 mm ceramic slab at a total pump power of 1215 W, corresponding to an optical-to-optical efficiency of 42.8%. An average small signal gain of 5.45 was achieved with a standard deviation of only 0.09 in the cross section, which shown good concentration uniformity. An average depolarization loss of 2.6% at different positions of the slab was obtained due to small thermal gradient of the zigzag configuration.

A full-aperture gain measurement obtained with the intensity ratio is presented for a diode-pumped ceramic slab laser amplifier. The small-signal gain profile of the amplifier is calculated by the ratio of pump-on and pump-off intensities. The distribution of absorbed pumping power, fluorescence distribution and gain in the width direction of the slab amplifier are simulated and measured, respectively. A gain homogeneity presented by standard deviation (σ) of 0.17 at a pump power of 1800 W is obtained in the experiment.

In this paper, an experiment is designed to research the properties of the stimulated Brillouin scattering phase conjugation mirror (SBS-PCM) working under joule-level pump energy and 200 Hz repetition rate. The nonlinear medium FC-770 is chosen as the SBS medium working in high-power condition. Due to the excellent preparation process and ultra-filtration technology for SBS-PCM, there is no optical breakdown phenomenon under the reflectivity maintained at 98% under 200 Hz and pump energy from 500 mJ to 1100 mJ. Under 800 mJ pump energy, the diffraction fringes of the near-field pattern are reduced and the beam quality of the laser beam has been improved to 1.42 times diffraction limited after the double-pass amplification from the single-pass 2.01 times diffraction limited. The incident and reflected pulse width are becoming wider with pump energy increasing. When the pump energy reaches a certain extent, the reflected pulse width will become nearly approximate to the incident pulse width. When the pump energy is 800 mJ, the pump pulse width is 40.3 ns and the output pulse width is 38.8 ns.

Utilizing structure-based drug design, a 4-aminoimidazole heterocyclic core was synthesized as a replacement for a 2-aminothiazole due to potential metabolically mediated toxicity. The synthetic route utilized allowed for ready synthesis of 1-substituted-4-aminoimidazoles. SAR exploration resulted in the identification of a novel cis-substituted cyclobutyl group that gave improved enzyme and cellular potency against cdk5/p25 with up to 30-fold selectivity over cdk2/cyclin E.

High-throughput screening with cyclin-dependent kinase 5 (cdk5)/p25 led to the discovery of N-(5-isopropyl-thiazol-2-yl)isobutyramide (1). This compound is an equipotent inhibitor of cdk5 and cyclin-dependent kinase 2 (cdk2)/cyclin E (IC50 = ca. 320 nM). Parallel and directed synthesis techniques were utilized to explore the SAR of this series. Up to 60-fold improvements in potency at cdk5 and 12-fold selectivity over cdk2 were achieved.