[en] A novel technique has been developed to lithographically make fine patterns on PZT films. Employing chemical modification in acetylacetone (AcAc), we have obtained an UV photosensitive PZT sol from which the PZT films to be patterned can be prepared. With methanol as solvent and AcAc as chemical modifier, three sols used to compose the PZT coating sol are obtained from Zirconium oxynitrate (ZrO(NO₃)₂), lead acetate (Pb(CH₃COO)₂), and tetrabutyl titanate ((C₄H₉O)₄Ti), respectively. By means of UV-vis and FT-IR spectrophotometers we have found that AcAc can associate with Zr, Pb, and Ti ions to form three chelate complexes, the UV absorption peaks of which are located at wavelength 304, 315 and 329 nm, respectively. However, the photosensitive PZT coating sol has UV absorption peak at around 312 nm. Both the chelate complexes in sol and the UV absorption peak can be remained in the gel films. When the photosensitive PZT gel film is irradiated by UV light containing 312 nm wavelength, its solubility in solvents such as alcohol, acetone and so on is reduced remarkably, while the UV absorption peak disappears with the dissociation of the chelate complexes correspondingly. Utilizing the characteristics, a fine pattern can be obtained by irradiation of UV light on the PZT gel film through a pattern mask and dissolving the non-irradiated area in suitable solvent. After annealing at 680 deg. C for 30 min, the PZT films with specific fine pattern can be obtained

[en] The photosensitive lanthanum-doped lead zirconate titanate (PLZT) gel films were prepared by chemical modification with acetylacetone (AcAcH), and their fourier transform infrared (FT-IR) spectra and ultraviolet visible (UV-Vis) spectra were measured. The results show that the chelate rings of AcAcH with Ti or Zr are formed in the PLZT gel films. With irradiation of UV light, the chelate rings are photolyzed, and lead to a change of the solubility of the PLZT gel films in methanol. Transmission electron microscope (TEM) observations show that the perovskite phase is crystallized in PLZT thin film after heat treatment at 700 deg. C, whose grain sizes are less than or equal to 60 nm. The PLZT thin films exhibited hysteresis loops and good fatigue properties

[en] A preconcentration neutron activation analysis method has been developed for determination of 14 rare earth elements in soil, sediment and some rock samples. The method involves sample melt together with Na₂O₂, coprecipitation and ion exchange. Unlike usual INAA, this method can greatly improve the sensitivity for the REE other than Er, Pr, Tm, Nd and Ho. The absolute detection limit depends on specific elements, the lowest is 8.4 ng for Eu and the highest 3.92 μg for Pr

[en] Graphical abstract: - Highlights: • A novel magnetic adsorbent SBPF for AF was obtained. • The adsorption is low pH- and temperature-dependent. • Several models were applied to study the kinetics and equilibrium parameters. • Hydrogen bond and ionic interactions were the main interactions. - Abstract: The hybrid magnetic Sr_5_xBa_3_x(PO_4)_3(OH)/Fe_3O_4 (SBPF) nanorod was prepared and characterized using different techniques, such as SEM, EDS, TEM, SAED, HRTEM, XRD, and FT-IR. Adsorption studies of acid fuchsin (AF) from aqueous solution with respect to the pH, temperature, time, initial dye concentration, and sorbent dosage were investigated. The Freundlich adsorption model was applied to describe the equilibrium isotherms. The maximal AF uptake by SBPF was 1590 mg/g in the test. Kinetics parameters of the adsorption process indicated that it followed the pseudo-second order equation, and the maximum sorption capacity calculated from the pseudo-second-order rate equation was 909 mg/g which was close to the experimental value. Adsorption thermodynamics study indicated the spontaneous nature and exothermic of the adsorption process. The removal of AF was attributed to the hydrogen bond and ionic interactions. Moreover, SBPF was easily recovered, and the adsorption capacity was approximately 97.7% of the initial saturation adsorption capacity after being used five times.

[en] Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may play a role in As detoxification. A major As-induced thiol was purified and characterized. A molecular ion (M+1) of 540 m/z suggests that the thiol was a phytochelatin (PC) with two base units (PC₂). However, the ratios of acid-soluble thiols to As in leaflets exposed to As ranged from 0.012 to 0.026, suggesting that only a very small part of As is complexed by PC₂. PCs could play a minor detoxification role in this hyperaccumulator. A PC-independent mechanism appears to be mainly involved in As tolerance, while PC-dependent detoxification seems to be a supplement

[en] Arsenic was predominantly present as inorganic arsenite in the fronds of the hyperaccumulator Chinese brake. - Arsenic speciation is important not only for understanding the mechanisms of arsenic accumulation and detoxification by hyperaccumulators, but also for designing disposal options of arsenic-rich biomass. The primary objective of this research was to understand the speciation and leachability of arsenic in the fronds of Chinese brake (Pteris vittata L.), an arsenic hyperaccumulator, with an emphasis on the implications for arsenic-rich biomass disposal. Chinese brake was grown for 18 weeks in a soil spiked with 50 mg As kg^-1 as arsenate (AsO₄^3-), arsenite (AsO₃^3-), dimethylarsinic acid (DMA), or methylarsonic acid (MMA). Plant samples were extracted with methanol/water (1:1) and arsenic speciation was performed using high performance liquid chromatography coupled with atomic fluorescence spectrometry. The impacts of air-drying on arsenic species and leachability in the fronds were examined in the laboratory. After 18 weeks, water-soluble arsenic in soil was mainly present as arsenate with little detectable organic species or arsenite regardless of arsenic species added to the soil. However, arsenic in the fronds was primarily present as inorganic arsenite with an average of 94%. Arsenite re-oxidation occurred in the old fronds and the excised dried tissues. Arsenic species in the fronds were slightly influenced by arsenic forms added to the soil. Air-drying of the fronds resulted in leaching of substantial amounts of arsenic. These findings can be of significance when looking at disposal options of arsenic-rich biomass from the point of view of secondary contamination

[en] In this study, a digital gamma–gamma coincidence/anticoincidence spectrometer was developed and examined for low-level cosmogenic "2"2Na and "7Be in air-filter sample monitoring. The spectrometer consists of two bismuth germanate scintillators (BGO) and an XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The spectrometer design allows a more selective measurement of "2"2Na with a significant background reduction by gamma–gamma coincidence events processing. Hence, the system provides a more sensitive way to quantify trace amounts of "2"2Na than normal high resolution gamma spectrometry providing a critical limit of 3 mBq within a 20 h count. The use of a list-mode data acquisition technique enabled simultaneous determination of "2"2Na and "7Be activity concentrations using a single measurement by coincidence and anticoincidence mode respectively. - Highlights: • A coin/anticoincidence spectrometer to measure "2"2Na and "7Be by list-mode acquisition. • The method provides a more sensitive way to quantify trace amounts of "2"2Na. • Compared with HPGe detector, critical limits improved by a factor 6–10. • "2"2Na and "7Be activity can be determined simultaneously using a single measurement

[en] As an enduring enigma of Neoproterozoic, the Cap Carbonate has been found in many regions of the world on lying on the glacial diamictites with negative carbon isotopic. There are many hypothesized explanations for this paleoclimatic dichotomy are high orbital obliquity, true polar wander, reduced solar luminosity, snowball albedo, CO_2 drawdown, stagnant ocean overturn, and reinterpretation of diamictites as mega-impact ejecta. The authors studied the Cap Carbonate in three different depositional environments in Guizhou Province, where the negative carbon isotopic was observed. The negative carbon isotopic in different depositional environments is different. The flatbedding at the lower part of the cap in the Tongren and Qingzhen regions can not be explained by the 'snow-ball' model. Furthermore, the crystal fans at lower part of the cap in the Tongren region exhibit soft-sediment deformational structures that may be attributed. To rebound-induced seismicity. The phenomena indicate the transition stage after the Marinoan glacial. Unconspicuous as it is, the transition stage in the other two regions can also be found. As shows the rapid icehouse to greenhouse transition in Snowball Earth. The transition stage may last 280,000 years by calculating. (authors)

[en] In this study, the aerosol activity concentrations of "2"1"0Pb at 28 Canadian radiological monitoring stations from 2009 to 2013 were analyzed. The results show that the ratio of "2"1"0Pb winter average concentration to summer average concentration increases with increasing latitude. This could be used to evaluate the transport of pollutants to the Arctic region such as the Arctic haze from Eurasia through long-range atmospheric transport during winter. Based on 12 years of monitoring results from the Yellowknife station that includes both "2"1"0Pb and "2"1"2Pb concentrations, the study confirms that the seasonal distribution of "2"1"0Pb to "2"1"2Pb activity concentration ratios has a significant peak in winter and a relatively low value in summer, which can be used as an indicator of the air mass flow to the Arctic. The period dominated by long-range aerosol transport and Arctic haze was estimated by fitting a Gaussian distribution function to the peak values of this ratio in winter. A peak width parameter of full width at half maximum (FWHM) allows a year by year estimate of the period of influence by long-range transport of aerosols, and this varied between 67 and 88 days in this study. The fitted Gaussian peak also shows that the season of the continental influenced air mass in Yellowknife usually starts in mid-to-late November and ends in mid-to-late April. Thus, the "2"1"0Pb to "2"1"2Pb ratio distributions may enable the determination of periods dominated by long-range aerosol transport and the scale of the Arctic haze at different latitudes. - Highlights: • Twelve years "2"1"0Pb/"2"1"2Pb monitoring results from low to high altitude are presented. • The "2"1"0Pb_w_i_n_t_e_r/"2"1"0Pb_s_u_m_m_e_r ratio increases clearly with latitude of monitoring site. • The pollutant transport to the Arctic is estimated by distribution "2"1"0Pb/"2"1"2Pb ratio. • The time scale of long-range transport aerosol bearing "2"1"0Pb to Arctic is reported

[en] A series of measurements have been recently conducted to determine the cosmic-muon intensities and attenuation factors at various indoor and underground locations for a gamma spectrometer. For this purpose, a digital coincidence spectrometer was developed by using two BC408 plastic scintillation detectors and an XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The results indicate that the overburden in the building at surface level absorbs a large part of cosmic ray protons while attenuating the cosmic-muon intensity by 20–50%. The underground facility has the largest overburden of 39 m water equivalent, where the cosmic-muon intensity is reduced by a factor of 6. The study provides a cosmic-muon intensity measurement and overburden assessment, which are important parameters for analysing the background of an HPGe counting system, or for comparing the background of similar systems. - Highlights: • A potentially new tool for cosmic-muon intensity and attenuation factor measurement. • Overburden estimation in the building at surface level and underground facility. • The reduction of cosmic-muon flux by employing plastic BC408 detectors. • The relationship between estimated overburden and muon attenuation factor.