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Zinc finger protein 804A (ZNF804A) has been identified by genome-wide association studies as a robust risk gene in schizophrenia, but how ZNF804A contributes to schizophrenia and its upstream regulation remains unknown. Previous studies have indicated that microRNAs (miRs) are key factors that regulate the expression levels of their target genes. The present study revealed significantly increased expression of miR-148b-3p in the peripheral blood of patients with first-onset schizophrenia compared with healthy controls, and bioinformatics analysis predicted that the ZNF804A gene is a target of miR-148b-3p. Therefore, the present study investigated the possible upstream regulation of ZNF804A by miR-148b-3p in the human neuroblastoma SH-SY5Y cell line, and assessed the implications for schizophrenia. The results revealed significantly reversed expression levels of miR-148b-3p (P=0.0051) and ZNF804A (P=0.0218) in the peripheral blood of patients with first-onset schizophrenia compared with healthy individuals. Furthermore, it was demonstrated that miR-148b-3p directly targeted ZNF804A via binding to conserved target sites in the 3′-untranslated region of ZNF804A mRNA, where it inhibited the endogenous expression of ZNF804A at both the mRNA (P=0.048) and protein levels (P=0.013) in SH-SY5Y cells. Furthermore, miR-148b-3p was revealed to regulate the expression levels of catechol-O-methyltransferase (COMT) and serine protease 16 (PRSS16) by targeting ZNF804A in SH-SY5Y cells. Collectively, the present results indicated that there was a direct upstream regulation of the schizophrenia risk gene ZNF804A by miR-148b-3p, which contributed to the regulation of the downstream genes COMT and PRSS16. Thus, the miR-148b-3p/ZNF804A/COMT/PRSS16 pathway may play an important role in the pathophysiology of schizophrenia, and may serve as a potential target in drug discovery and gene therapy for this disorder.

Hollow cathode discharge in He/O2 mixed gas is simulated using a two-dimensional fluid model for the first time. The model contains 15 particles and 66 reactions. The evolutions of discharge current, electric field, charged and reactive particles with different oxygen concentrations are obtained. The primary mechanisms of generation and loss for particles under different oxygen concentrations are discussed. The results show that the added O2 in helium has both positive and negative effects on the discharge. The discharge does not monotonically change with the increasing oxygen concentration. When the oxygen concentration is low, oxygen admixture could enhance the discharge, that is, the discharge current, radial electric field, electron density, O 2 + density, O density, and the O(1D) density increase with the increase of oxygen concentration. When the oxygen concentration is high, it will weaken discharge, that is, the discharge current, radial electric field, electron density, O 2 + density, O density, and the O(1D) density decrease with the increase of oxygen concentration. The main reactive particles in discharge are O and O(1D). These densities are much higher than the density of charged particles. The optimal oxygen concentration for O and O(1D) is 0.5% and 0.4%, and the corresponding maximum density is 4.34 × 1013 cm−3 and 1.50 × 1013 cm−3. The generation and loss rates for these particles at different oxygen concentrations are calculated, which contributes to the change in particle densities.

NMDA receptors play an important physiological role in regulating synaptic plasticity, learning and memory. GluN2A subunits are the most abundant functional subunits of NMDA receptors expressed in mature brain, and their dysfunction is related to various neurological diseases. According to subunit composition, GluN2A-containing NMDA receptors can be divided into two types: diheteromeric and triheteromeric receptors. In this review, the expression, functional and pharmacological properties of different kinds of GluN2A-containing NMDA receptors as well as selective GluN2A regulators were described to further understand this type of NMDA receptors.

Much evidence has proved that excitotoxicity induced by excessive release of glutamate contributes largely to damage caused by ischemia. In view of the key role played by NMDA receptors in mediating excitotoxicity, compounds against NMDA receptors signaling pathways have become the most promising type of anti-stroke candidate compounds. However, the limited therapeutic time window for neuroprotection is a key factor preventing NMDA receptor-related compounds from showing efficacy in all clinical trials for ischemic stroke. In this perspective, the determination of therapeutic time windows of these kinds of compounds is useful in ensuring a therapeutic effect and accelerating clinical application. This mini-review discussed the therapeutic time windows of compounds against NMDA receptors signaling pathways, described related influence factors and the status of clinical studies. The purpose of this review is to look for compounds with wide therapeutic time windows and better clinical application prospect.

With the continuous development and expansion of the city, the industrial center of the city has gradually shifted to the emerging industrial area or the outskirts. The industrial building remains that were originally located in the city center have been left behind. The development of the site often adopts the development method of "buy the casket without the jewels ", while the development method of "buy the casket with the jewels "is few, and which development method is more valuable.Taking Laolongkou distillery as an example, this paper makes a comparative analysis in order to provide reference for the site development of industrial building remains.

This paper discusses the establishment and construction of characteristic towns at all levels in Liaoning Province, including 13 national characteristic towns, 20 provincial characteristic villages and towns and 11 industrial characteristic towns, and then analyzed the problems and obstacles encountered in the construction of these towns, puts forward some suggestions and strategies to solve these problems, in order to provide some reference for the construction of characteristic towns in Liaoning Province.

Two new compounds were extracted and separated from the whole plant of Aleuritopteris argentea . The structures and absolute configurations of two compounds were characterized by UV, FT-IR, NMR, MS, and single-crystal X-ray diffraction. Compound 1 was determined to be 2, 17-diol (2β, 4α)-15,16-ene-beyerane diterpenoid and compound 2 to be 2,18-diol (2β, 4α)-16-ene-ent-kaurane diterpenoid, named aleuritopsis A and aleuritopsis B respectively. The cytotoxicity of two compounds against MCF-7 and SKOV3 cells were tested using the MTT method, as the results, both exhibited obvious inhibitory effect to the tumor cells.

In this paper, airborne and spaceborne SAR technology is used to study the signal broadband technology and imaging algorithm. For high recognition low orbit spaceborne SAR technology, we describe the method to improve the recognition rate in the case of multi direction and multi-channel. For Airborne SAR, we study tops8 imaging processing algorithm. For airborne squint short range low resolution SAR, we design the imaging place that can be used at any time For geosynchronous orbit SAR, we use relativity and satellite launch theory to observe the laser and recognition rate, and design a data model suitable for geosynchronous orbit satellite imaging processing. Because of the huge amount of information and complex processing process in imaging processing, we collect and calculate the key data on the basis of BP data model. After many experiments, we find that this method is efficient and simple, and the GPU system is optimized and upgraded through BP model, which improves the recognition rate after imaging. Therefore, we think this method can achieve large-scale imaging Part of SAR imaging processing.

A new method using solid phase extraction (SPE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the determination of six polyether antibiotics, including lasalocid, salinomycin, monensin, narasin, madubamycin and nigericin residues, in foods of animal origin. The samples were extracted with acetonitrile and purified by ENVI-Carb SPE columns after comparing the impurity effect and maneuverability of several SPE cartridges. Subsequently, the analytes were separated on a Hypersil Gold column (2.1×150mm, 5μm) and analyzed by MS/MS detection. The limit of quantization (LOQ) for milk and chicken was 0.4μg/kg, and for chicken livers and eggs, it was 1μg/kg. The linearity was satisfactory with a correlation coefficient of >0.9995 at concentrations ranging from 2 to 100μg/L. The average recoveries of the analytes fortified at three levels ranged from 68.2 to 114.3%, and the relative standard deviations ranged from 4.5 to 12.1%. The method was suitable for quantitative analysis and confirmation of polyether antibiotic residues in foods of animal origin.

A large-volume glow discharge is produced using a microhollow cathode sustained discharge (MCSD) with a needle-plate second anode in argon. The length and volume of the glow discharge are approximately 3 cm and 7 cm3, respectively, and the electron density is on the order of 1011 cm−3. The MCSD is also simulated using a two-dimensional self-consistent fluid model with a single plate as the second anode. Both the experimental and simulated results show that MCSD generation originates from cooperative formation that involves the microhollow cathode discharge and a discharge that arises from the second anode. The second anode plays an important role in MCSD generation. The electric field and the average electron energy clearly increase in the region near the second anode. The influence of the structure of the second anode on the MCSD characteristics is investigated. When the second anode has a needle-plate structure instead of a single plate structure, the sustaining voltage, breakdown, and annihilation current of the cathode for MCSD decrease substantially, a higher discharge current is obtained, and a more stable, uniform MCSD is produced. The results also show that both needle and plate contribute to glow discharge formation in the region near the second anode.

This paper presents experimental results of the characteristics appearance and the mechanism of self-oscillation in a parallel-plate glow discharge with argon as the discharge gas at 266 Pa. The cathode and anode are molybdenum plates with a diameter of 3 cm. The distance between the electrodes is 1 cm. Discharge average voltage and current vary between 300 V and 500 μA, respectively. Light emission from the electrode gap is measured by a charge coupled device camera and argon spectra are recorded of emission lines at 650–800 nm. Results show that self-oscillations exist in the negative differential resistance region in the static V–I curve. An obvious negative differential resistance also can be observed in the dynamic of the V–I curve for the self-oscillations. The appearance and disappearance of the self-oscillating phenomenon are companied with an obvious change in all of the discharge current, discharge images, and electron excited temperature. It can be determined that the self-oscillation is a mode transition between low-current stage of Townsend discharge and high-current stage of glow discharge. The frequency range of self-oscillations starts with 0.4 k Hz up to 24 k Hz in dependence of the average discharge current and the external capacitors. When the self-oscillation disappears, the luminescence shows a significant radial contraction, the electron excitation temperature rise obviously. The frequency of oscillations exhibits a substantial linear increase with the average discharge current and decreases with the increase in the external capacitance from 0 pF up to 250 pF. A resistance–capacitance circuit model is used to simulate the self-oscillation discharge in this experimental glow discharge. Results show that the waveforms simulated by this circuit model are well consistent with those obtained experimentally at different average discharge currents and external parallel capacitances. The equivalent plasma resistance decreases with an increase in the average discharge current. The theory of charge and discharge of a capacitor provides good insights into the characteristics and mechanism of self-oscillations in parallel-plate discharges.

As an old industrial base in the country, Liaoning Province has a solid industrial foundation. The development of industrial tourism in Liaoning Province can not only accelerate the promotion of new industrialization roads, but also contribute to the healthy and sustainable development of the tourism industry in Liaoning Province. This paper analyzes the obstacles and problems in the development of industrial tourism in Liaoning Province at the current stage, and proposes a series of countermeasures to promote the development of industrial tourism in Liaoning Province, which provides ideas for the development and revitalization of industrial tourism.

Background Although pneumonia is a known cause of morbidity and mortality in Sarawak, Malaysia, the etiology and epidemiology of pneumonia are not well described in this equatorial region. Routine clinical diagnostics for pneumonia etiology at government hospitals in Sarawak had historically involved only bacterial diagnostics. Viral diagnostics were only obtained through outside consultations. Methods From June 15, 2017 to May 14, 2018, we collected nasopharyngeal swabs from 600 patients of all ages older than 1 month hospitalized with pneumonia at Sibu and Kapit Hospitals. Specimens were examined at our collaborating institutions with a panel of molecular assays for viral pathogens including influenza A (IAV), IBV, ICV, and IDV, human adenovirus (AdV), human enterovirus (EV), human coronavirus (CoV), respiratory syncytial virus subtype A (RSV-A) or RSV-B, and parainfluenza virus (PIV) types 1–4. Results Of 599 samples examined, 288 (48%) had molecular evidence of 1 or more respiratory viruses. Overall, the most prevalent virus detected was RSV-A (14.2%) followed by AdV (10.4%) and IAV (10.4%), then RSV-B (6.2%), EV (4.2%), IBV (2.2%), PIV-3 (1.7%), CoV (1.0%), PIV-1 (1.0%), PIV-4 (0.7%), and PIV-2 (0.2%). No specimens were confirmed positive for ICV or IDV. Conclusions The high prevalence of viruses detected in this study suggest that respiratory viruses may be responsible for considerable morbidity in equatorial regions such as Sarawak. Access to viral diagnostics are very necessary for medical staff to determine appropriate pneumonia treatments.

Based on a conical bubble U-tube, conical bubble sonoluminescence was investigated by using pure water as the working medium. Intense cavitation luminescence can be obtained. With the decrease in initial pressure inside the bubble, the intensity and duration of light emission increased. The spectrum is mainly composed of the spectral bands of H 2 O at the initial pressure of 1000 Pa. With the decrease in initial pressure, a broad continuum background spectrum that is well fitted by blackbody radiation can be detected, on which several spectral bands emitted by water molecules are superimposed. A higher temperature inside the bubble can be obtained with the decrease in initial pressure. Moreover, the intensity of the continuum background spectrum becomes more dominant compared with that of H 2 O emission bands. Finally, we conclude that blackbody radiation and molecular emission contribute to luminescence of conical bubble cavitation. Moreover, the initial pressure inside the conical bubble significantly affects the emission mechanism of conical bubble sonoluminescence.

The main object of the present invention is to provide an improved process for the preparation of Iloperidone, which would be more simple, economical and easy to implement on large scale preparation. In this paper, 1,3-difluorobenzene and 1-(4-hydroxy-3-methoxyphenyl) ethanone are starting materials. And then tartaric acid is added. The key intermediate (Z)-4-(2,4-difluorobenzoyl) piperidine oxime is obtained through stereoselectivity. With the key intermediate and 1-(4-(3-chloropropoxy)-3-methoxyphenyl) ethanone, the target product is obtained directly under the condition of catalyst.

Oxadiazole as a class of five-membered heterocycles has been reported to be biologically versatile compounds due to their metabolic profile. Amongst these heterocycles, 1,3,4oxadiazole has become an important construction motif for the development of new drugs, furamizole as antibiotics, tiodazosin as antihypertensive agent and raltegravir as antiretroviral agent have been on market. In addition, 2,5-disubstituted-1,3,4-oxadiazole derivatives have also been used as electron conducting and hole blocking (ECHB) materials for electron deficient and good electron transport properties of oxadiazole rings. The most common synthetic approach to 1,3,4-oxadiazoles involves cyclodehydration of 1,2-diacylhydrazines 3 (Scheme 1). Typically, this reaction is carried out by using SOCl2, 5 POCl3, 6 as well as others. Although these methods are very useful for the preparation of large quantities of materials due to the ready availability of diacylhydrazines, hydrazides, and hydrazones as starting materials, the reaction conditions tend to be harsh and long reaction times are generally needed. An alternative route to 1,3,4-oxadiazoles 2 by oxidative cyclization from the corresponding aldehyde N-acylhydrazones 1 proceeds (a) with transition metal oxidants such as Pb, Mn, Fe, Ce or Cu et al.; (b) with chloramine T, Trichloroisocyanuric Acid, iodobenzene diacetate (IBD), Dess–Martin reagent (DMP) or other oxidants; (c) electrochemical methods (Scheme 1). To the best of our knowledge, preparation of 1,3,4-oxadiazoles utilizing iodosobenzene as the oxidizing agent has not been reported yet. In our continuous research program of the oxidation of hypervalent iodine, we were interested in the development of robust and general method to access functionalized 2,5-disubstituted-1,3,4-oxadiazoles. It was found that aromatic aldehyde N-acylhydrazones 1 reacted with (PhIO)n/BF3·Et2O at room temperature to efficiently afford 2,5-disubstituted-1,3,4-oxadiazoles 2 in mild to good yields (Scheme 2). The polymeric character of iodosobenzene makes it less suitable as oxidant than other hypervalent reagents, mainly because of its insolubility in ordinary solvents. Its utility is, however, greatly enhanced when it is used with catalysts, notably boron trifluoride. The electrophilic character of iodine in iodosobenzene is greatly increased by the addition of boron trifluoride, probably because of the in-situ formation of the monomeric dipole PhI+-OBF3 −. N'-Benzylidenefuran-2-carbohydrazide (1a) was chosen as the substrate in initial studies (Table 1). When the substrate

This study aims to establish quality standards of Aleuritopteris Herba (AH), which could supply scientific evidence for the quality control of AH. The morphological and microscopic identification characters were reformulated. The tests of water content, total ash, acid-insoluble ash and ethanol-soluble extractives of AH were carried out according to the methods recorded in appendix of Chinese Pharmacopeia (2010 edition, volume 1). The TLC method was established by using aleuritopesis A [2,19-diol（2β,4α）-16-enekaureniod] and reference herb as references. With preparation of aleuritopesis A[2,19-diol（2β,4α）-16-enekaureniod] reference substance, the content of aleuritopesis A in AH was determined by HPLC. As a result, the macroscopic identification, microscopic features and TLC methods were specific and simple. The water content, total ash, acid-insoluble ash and ethanol-soluble extractive and the content of aleuritopesis A of all samples varied in the ranges of 8.8%-10.9%, 7.6%-11.4%, 2.5%-4.2%, 9.3%-10.2% and 0.56%-0.71%, respectively. The improved quality standard can be used to evaluate and guarantee the quality of AH comprehensively.

Through the design of the Laolongkou distillery Sustainable protection research, The author get the method about latent economic benefits in excavation culture, provides a new road for other local historical heritage constructive protection development. Firstly, the Distillery heritage cannot be changed and want to bring economic value. This creates a contradiction, and how to make living environment and Distillery production environment not contradiction. The authors adopt a "platform" idea. Secondly, sustainable development of distillery culture characteristics. There are a lot of cultural relics and intangible cultural heritage, use these elements improve tourism environment level and quality, show distillery industrial heritage characteristic, obtain industrial tourism economic and cultural benefits.

The construction of Marshal Zhang’ Mansion experienced three periods. A three-Courtyard was building from 1914 to 1918. Big-blue building was built in the early 1920s and Small-blue building was built before the early 1920s. Six red brick buildings were built after 1929. The three groups of buildings in the three periods condense that modern architectures how to evolve in Shenyang from 1912 to 1931，including of technology，material and style. Therefore, as long as we understand the developmental characteristics of buildings’ in Marshal Zhang’ Mansion， we can grasp the evolutionary law of modern architectures in Shenyang in this period. So Marshal Zhang’ Mansion has great significance to the architectural history in Shenyang.

The Red Buildings is going to be incorporated into the Marshal Zhang’ Mansion memorial which exhibits as the State-level key cultural relics protection unit. It will be an important component of the whole exhibition. We based the design on the research of design orientation and function conversion. After studied the history of the buildings and analyzed the differences between the old and the new functions, we made a principle of less change. First, we set two different routes for the visitors and the vehicles in the Red Building. And the visitors’ route was connected whit the tour route of Marshal Zhang’ Mansion memorial closely. Second, we set up one tour axis with four landscape nodes and two landscape axes inside the Red Buildings. They will outstanding original condition and show nice scenes of the whole buildings to visitors.

Background The large livestock operations and dense human population of Southeast Asia are considered a hot-spot for emerging viruses. Objectives To determine if the pathogens adenovirus (ADV), coronavirus (CoV), encephalomyocarditis virus (EMCV), enterovirus (EV), influenza A-D (IAV, IBV, ICV, and IDV), porcine circovirus 2 (PCV2), and porcine rotaviruses A and C (RVA and RVC), are aerosolized at the animal-interface, and if humans working in these environments are carrying these viruses in their nasal airways. Study This cross-sectional study took place in Sarawak, Malaysia among 11 pig farms, 2 abattoirs, and 3 animal markets in June and July of 2017. Pig feces, pig oral secretions, bioaerosols, and worker nasal wash samples were collected and analyzed via rPCR and rRT-PCR for respiratory and diarrheal viruses. Results In all, 55 pig fecal, 49 pig oral or water, 45 bioaerosol, and 78 worker nasal wash samples were collected across 16 sites. PCV2 was detected in 21 pig fecal, 43 pig oral or water, 3 bioaerosol, and 4 worker nasal wash samples. In addition, one or more bioaerosol or pig samples were positive for EV, IAV, and RVC, and one or more worker samples were positive for ADV, CoV, IBV, and IDV. Conclusions This study demonstrates that nucleic acids from a number of targeted viruses were present in pig oral secretions and pig fecal samples, and that several viruses were detected in bioaerosol samples or in the nasal passages of humans with occupational exposure to pigs. These results demonstrate the need for future research in strengthening viral surveillance at the human-animal interface, specifically through expanded bioaerosol sampling efforts and a seroepidemiological study of individuals with exposure to pigs in this region for PCV2 infection.

The stimulative action and detoxifying effect of selenium on garlic growth under cadmium stress were investigated. Selenite treatment can promote mitosis of garlic root-tip cells and growth of roots and seedlings. Garlic has a strong ability to accumulate the selenium from soil, and selenium content was greatest in garlic seedlings. Addition of selenite at a concentration of 2.0 μg kg−1 in soil could decrease cadmium content in garlic and protect the seedling growth. The selenium has been shown to have an effective protective role on garlic growth under cadmium stress.

A method has been developed for the generation of a “cold vapor” of cadmium by means of continuous flow chemical vapor generation from aqueous samples and for use in derivative atomic absorption spectrometry. Variables such as acidity, reducing agent concentration, atomization temperature, argon flow rate, reaction coil length, and other parameters were optimized. Detection limits and repeatability were measured, and cadmium was also determined in certified reference material and in tap water. The results showed that the proposed automated method is simple and accurate with a detection limit of 0.021 ng mL−1 when the derivative system’s sensitivity was 2 mV min−1

The species of Cr(III) and Cr(VI) in water samples were determined by flow injection on-line preconcentration and separation on two-microcolumn system-derivative flame atomic absorption spectrometry during a collaborative analysis for certification. The Cr(III) and Cr(VI) in water samples were retained on two microcolumns with ion exchange resin and were eluted directly to nebulizer by 15% HNO3 and 8% NH4NO3, respectively. The characteristic concentration (at the sensitivity grade of 2 mV min−1 for 1 min of preconcentration time) for Cr(III) and Cr(VI) were 0.130 and 0.0985 μg l−1, in the order which were 332- and 431-fold better than those of FAAS, and 45- and 47-fold better than those of FI-FAAS, respectively. The relative standard deviations were 3.27% and 3.66% with corresponding detection limits (3σ) of 0.244 and 0.235 μg l−1, respectively. The linear ranges of determinations for Cr(III) and Cr(VI) were 0∼100 μgm l−1 with correlation coefficients of 0.9984 to 0.9996. The satisfactory recovery of 94.4%∼106% for Cr(III) and Cr(VI) could be obtained from water samples.

The characteristics of striations in cylindrical hollow cathode discharge were investigated experimentally. The spectra of striations were measured at a pressure of 20 Pa in a discharge of 1.3 mA, in which the main spectra are the emission spectrum lines of the N2 first positive band (B3pi(g)--A3pi(u)) and second positive band system (C3pi(u)--B3pi(g)). The spatial characteristics of vibrational temperature of N2 were calculated based on the theory of double molecular spectrum. It is shown that the emission intensity exhibits a periodic structure with an unequal magnitude, and the spectral intensity of bright striation is higher than that of dark striations. The vibrational temperature of bright striation is of the value of 3500-4400K, moreover the vibrational temperature in the bright regions decreases from the cathode to the anode. In addition, the characteristics of striations at 1.0 mA and 1.5 mA were obtained, and the influence of discharge current on the striations was investigated. It is shown that the vibrational temperature and the distance between two striations increase. Finally the reduced electric field was calculated, which is about 44 approximately 49 m(-1) x Pa(-1), moreover it decreases with the increase in discharge current. The results are very useful for understanding the mechanism of discharge striations and for improving the stability of hollow cathode discharge.

A new complex, [Pb2(H2O)2(HBTC)2] · 3H2O (H3BTC = 1,3,5-Benzenetricarboxylic acid) (1), has been synthesized under hydrothermal condition. The single-crystal analysis shows that 1 consists of 1-D double-chains with Pb(II) six-coordinated by three H3BTC and one H2O molecule with the Pb–O bond distances in the range of 2.56–2.76 A. When the Pb–O bonding limit extends from 2.76 to 2.90 A, the potential weak bonds of Pb–O can be found and the coordination number of Pb will increase from six to nine. As a result, the coordination geometry of Pb(II) transforms from hemidirected to holodirected and an infinite 3-D framework is obtained by the connection of the double-chains. The IR spectrum and the TGA–DTA curve of 1 are also reported in this paper.

Oxadiazole as a class of five-membered heterocycles has been reported to be biologically versatile compounds due to their metabolic profile. Amongst these heterocycles, 1,3,4oxadiazole has become an important construction motif for the development of new drugs, furamizole as antibiotics, tiodazosin as antihypertensive agent and raltegravir as antiretroviral agent have been on market. In addition, 2,5-disubstituted-1,3,4-oxadiazole derivatives have also been used as electron conducting and hole blocking (ECHB) materials for electron deficient and good electron transport properties of oxadiazole rings. The most common synthetic approach to 1,3,4-oxadiazoles involves cyclodehydration of 1,2-diacylhydrazines 3 (Scheme 1). Typically, this reaction is carried out by using SOCl2, 5 POCl3, 6 as well as others. Although these methods are very useful for the preparation of large quantities of materials due to the ready availability of diacylhydrazines, hydrazides, and hydrazones as starting materials, the reaction conditions tend to be harsh and long reaction times are generally needed. An alternative route to 1,3,4-oxadiazoles 2 by oxidative cyclization from the corresponding aldehyde N-acylhydrazones 1 proceeds (a) with transition metal oxidants such as Pb, Mn, Fe, Ce or Cu et al.; (b) with chloramine T, Trichloroisocyanuric Acid, iodobenzene diacetate (IBD), Dess–Martin reagent (DMP) or other oxidants; (c) electrochemical methods (Scheme 1). To the best of our knowledge, preparation of 1,3,4-oxadiazoles utilizing iodosobenzene as the oxidizing agent has not been reported yet. In our continuous research program of the oxidation of hypervalent iodine, we were interested in the development of robust and general method to access functionalized 2,5-disubstituted-1,3,4-oxadiazoles. It was found that aromatic aldehyde N-acylhydrazones 1 reacted with (PhIO)n/BF3·Et2O at room temperature to efficiently afford 2,5-disubstituted-1,3,4-oxadiazoles 2 in mild to good yields (Scheme 2). The polymeric character of iodosobenzene makes it less suitable as oxidant than other hypervalent reagents, mainly because of its insolubility in ordinary solvents. Its utility is, however, greatly enhanced when it is used with catalysts, notably boron trifluoride. The electrophilic character of iodine in iodosobenzene is greatly increased by the addition of boron trifluoride, probably because of the in-situ formation of the monomeric dipole PhI+-OBF3 −. N'-Benzylidenefuran-2-carbohydrazide (1a) was chosen as the substrate in initial studies (Table 1). When the substrate

An improved conical bubble sonoluminescence U-tube was built. Using this setup, the spectra and light pulses of conical bubble luminescence in glycerin were detected. Results show that the spectra are continuum, which are well fitted by blackbody radiation. The cavitational temperature ranging from 2 600 to 3 050 K was calculated from the fitted spectra. The reasons for the existence of blackbody radiation in conical bubble luminescence were discussed both from special and temporal sides. The value of radius of cavitational bubble is about 1.7 cm theoretically, which is greater than that of the bubble acoustically excited. The width of light pulses of cavitational bubble reached 40-60 ms, and this provided enough time for the blackbody radiation. In addition, the light pulses at different wavelength were measured, and results show that the width of light pulses increased with the raise of wavelength of spectra, which proved the mechanism of blackbody radiation. Finally, based on the spectra and light pulses, the intensity of luminescence was calculated to be about 0.18 J.

Based on the U-tube, a new type of sonoluminescence apparatus-conical bubble sonoluminescence straight tube apparatus was set up, and the structures and operations were described detailedly. Using the apparatus, the ultrabright cavitation luminescence was obtained in glycol solution. The light pulses of conical bubble sonoluminescence were detected, results show the half width is about 80 micros that is much longer than the results by ultrasound, which should be caused by the fact that the conical bubble can obtain more energy from the flow than the bubbles from the ultrasound. The spectra consist in a broad background ranging from the ultraviolet region to the visible region, on which five clear sequences of Swan bands and three sequences of B 2sigma+ --X 2sigma+ transition of CN are superimposed. A band assigned to the A 2delta --X 2II transition of CH was also measured. Specially, the vibrational structures of Swan bands can be resolved. Finally, the achieved molecular vibrational temperature of C2 is estimated to be about (4 200 +/- 200) K.

In an attempt to inhance the emission intensity of ICP, a conventional concentric pneumatic nebulizer was used with increased pressure, and the aqueous aerosol was partially let out to modulate the flow velocity of sample solution into the flame of the ICP. In the present work, the emission spectra of elements Ca, Si, Sr and Zn in water samples were measured, and the results showed that corresponding emission intensities are the highest at 0.05 MPa under the conventional condition, and after increasing the nebulizer gas pressure to 0.07 MPa and letting out part of aqueous aerosol, the peak values grew by 38%, 79%, 45% and 70%, respectively. In addition, the stability of the plasma radiation was not affected by the higher nebulizer gas pressure.

The effect of solution temperature (20, 40 and 60 degrees C) on the emission intensity of ICP has been studied. The results show that the spectrum intensity of the elements Ba, Cu and Zn increases obviously with increasing the solution temperature. In addition, at different solution temperatures, the rule of the variation of the intensity with both observation height and nebulizer gas pressure has been obtained, which indicates that the best observation location is lowered when increasing the temperature, but the best nebulizer gas pressure is augmented.