Effect of Water Vapor Absorption on Measurements of Atmospheric Nitrate Radical by LP-DOAS

During the measurement of atmospheric nitrate radical by long-path differential optical absorption spectroscopy, water vapor strong absorption could affect the measurement of nitrate radical and detection limits of system. Under the tropospheric condition, the optical density of water vapor absorption is non-linearly dependent on column density. An effective method was developed to eliminate the effect of water vapor absorption. Reference spectra of water vapor based on the daytime atmospheric absorption spectra, when fitted together with change of cross section with water vapor column densities, gave a more accurate fitting of water vapor absorptions, thus its effect on the measurements of nitrate radical could be restricted to a minimum and detection limits of system reached 3.6 ppt. The modified method was applied during an intensive field campaign in the Pearl River Delta, China. The NO3 concentration in polluted air masses varied from 3.6 ppt to 82.5 ppt with an average level of 23.6±1.8 ppt.

Transcription factor Dmrt1 triggers the SPRY1-NF-κB pathway to maintain testicular immune homeostasis and male fertility

Bacterial or viral infections,such as Brucella,mumps virus,herpes simplex virus,and Zika virus,destroy immune homeostasis of the testes,leading to spermatogenesis disorder and infertility.Of note,recent research shows that SARS-CoV-2 can infect male gonads and destroy Sertoli and Leydig cells,leading to male reproductive dysfunction.Due to the many side effects associated with antibiotic therapy,finding alternative treatments for inflammatory injury remains critical.Here,we found that Dmrt1 plays an important role in regulating testicular immune homeostasis.Knockdown of Dmrt1 in male mice inhibited spermatogenesis with a broad inflammatory response in seminiferous tubules and led to the loss of spermatogenic epithelial cells.Chromatin immunoprecipitation sequencing(ChIP-seq)and RNA sequencing(RNA-seq)revealed that Dmrt1 positively regulated the expression of Spry1,an inhibitory protein of the receptor tyrosine kinase(RTK)signaling pathway.Furthermore,immunoprecipitation-mass spectrometry(IP-MS)and co-immunoprecipitation(Co-IP)analysis indicated that SPRY1 binds to nuclear factor kappa B1(NF-κB1)to prevent nuclear translocation of p65,inhibit activation of NF-κB signaling,prevent excessive inflammatory reaction in the testis,and protect the integrity of the blood-testis barrier.In view of this newly identified Dmrt1-Spry1-NF-κB axis mechanism in the regulation of testicular immune homeostasis,our study opens new avenues for the prevention and treatment of male reproductive diseases in humans and livestock.

Effect of Atmospheric Interfering Absorption on Measurement of BTX by DOAS

It was reported on the elimination of interfering absorption of BTX. the absorption of O2 includes different absorption bands, which change differently when the partial pressure of oxygen is varied. These cause the nonlinear absorption of O2 and the observed band shape to vary with the column density of O2. The absorption ratios of molecular absorption in each of the Herzberg bands and dimer absorptions, as well as the contribution to the correction error of molecular absorption, are studied based on the characteristic of these absorption bands. The optimized way to eliminate the interfering absorption is obtained in the end and the effectiveness of using interpolation proposed by Volkamer et al. to remove O2 absorption is proved again. As to O2 and SO2, the effect of the thermal effect of characteristic spectra on the elimination error of their absorption is studied. Solutions to these problems are discussed and demonstrated together with methods to optimize the interpolation of spectra. As a sample application, differential optical absorption spectroscopy （DOAS） measurements of BTX are carried out. Results show a low detection limit and the good correlation with point instruments are achieved. All these prove the feasibility of using spectral interpolation to improve the accuracy of DOAS measurements of aromatic hydrocarbons for practical purposes.

An Interactive Network Laboratory for Electronic Engineering Education

The advantage of the network laboratory is the better flexibility of lab experiments by allowing remote control from different locations at a freely chosen time. In engineering education, the work should not only be focused on the technical realization of virtual or remote access experiments, but also on the achievement of its pedagogical goals. In this paper, an interactive laboratory is introduced which is based on the online tutoring system, virtual and remote access experiments. It has been piloted in the Department of Electronic Science and Technology, HUST. Some pedagogical issues for electronic engineering laboratory design, the development of a multi-serverbased distributed architecture for the reduction of network latency and implementations of the function module are presented. Finally, the system is proved valid by an experiment.

Solution-processed CuOx as an efficient hole-extraction layer for inverted planar heterojunction perovskite solar cells

A solution-processed CuOx film has been successfully integrated as the hole-transporting layer（HTL） for inverted planar heterojunction perovskite solar cells（PVSCs）. The CuOx layer is fabricated by simply spin-coating a copper acetylacetonate（Cu（acac）2） chloroform solution onto ITO glass with high transparency in the visible range. The compact and pinhole-free perovskite film with large grain domains is grown on the CuOx film. The inverted PVSCs with the structure of ITO/CuOx/MAPbI3/PC（61）BM/ZnO/Al are fabricated and show a best PCE of 17.43% under standard AM 1.5G simulated solar irradiation with a VOCof 1.03 V, aJ（SC） of 22.42 mA cm^（-2）, and a fill factor of 0.76, which is significantly higher and more stable than that fabricated from the often used hole-transporting material PEDOT：PSS（11.98%） under the same experimental conditions. The enhanced performance is attributed to the efficient hole extraction through the CuOx layer as well as the high-quality CH3NH3PbI3 films grown on the CuOx. Our results indicate that low-cost and solution-processed CuOx film is a promising HTL for high performance PVSCs with better stability.

Water Soluble Amino Grafted Silicon Nanoparticles and Their Use in Polymer Solar Cells

Stable aqueous amino-grafted silicon nanoparticles （SiNPs-NH2） were prepared via one-pot solution method. By grafting amino groups on the particle surface, the dispersion of SiNPs in water became very stable and clear aqueous solutions could be obtained. By incorporating SiNPs-NH2 into the hole transport layer of poly（3,4- ethylenedioxythiophene）/polystyrene sulfonic acid （PEDOT＇PSS）, the performance of polymer solar cells composed of poly[2-methoxy,5-（2＇-ethylhexyloxy）-1,4-phenylene vinylene] （MEH-PPV）：[6,6]-phenyl-C61-butyric acid methyl ester （PCBM） as active layer can be improved. SiNPs-NH2 are dispersed uniformly in the PEDOT：PSS solution and help form morphologies with small-sized domains in the PEDOT：PSS film. SiNPs-NH2 serve as screens between conducting polymer PEDOT and ionomer PSS to improve the phase separation and charge transport of the hole transport layer. As a result, the sheet resistance of PEDOT：PSS thin films is decreased from （93 ±5） × 10^5 to （13 ± 3） × 10^5 Ω/□. The power conversion efficiency （PCE） of polymer solar cells was thus improved by 9.8% for devices fabricated with PEDOT＇PSS containing 1 wt% of SiNPs-NH2, compared with the devices fabricated by original PEDOT：PSS.

Improved Photovoltaic Performance from High Quality Perovskite Thin Film Grown with the Assistance of PC71BM

The strategy of sequentially spin-coating a perovskite film from the perovskite precursor and an electron transporting layer of [6,6]-phenyl-C71-butyric acid methyl ester （PC71BM） is developed to simplify the fabrication procedure of perovskite solar cells. X-ray diffraction and scanning electron microscopy indicate that PCTIBM film on perovskite layer can retard the evaporation of dimethyl sulfoxide （DMSO） efficiently, thus prolonging the transformation of intermediate phase to perovskite crystals, leading to a high quality perovskite thin film. The solar cells with the structure of indium tin oxides （ITO）/poly（3,4-ethylenedioxythiophene）：poly（styrenesulfonate） （PEDOT：PSS）/CH3NH3PbI3/PC71BM/bathocuproine （BCP）/Ag made from this simplified method exhibit a higher efficiency （12.68%） than those from the conventional one-step method （9.49%）.