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The hierarchical porous composites (Beta/Dt) were prepared by secondary growth method using natural diatomite and beta zeolite. Moreover, XRD, SEM, and BET characterize the composite's composition, surface structure, and pore structure. The adsorbability of Beta/Dt was evaluated by adsorption of three common volatile organic compounds (VOCs) of the printing industry: acetone, ethyl acetate, and toluene. The results show that under the optimum preparation condition, the adsorption capacities of the three VOCs on Beta/Dt were about 3.5 times those of pure beta zeolite and 4.7-35.3 times those of diatomite, respectively. It indicates the synergistic adsorption effect between beta zeolite and diatomite. The superior adsorption capacity of Beta/Dt can be attributed to the suitable micropore size, the increase of the diffusion channels, and the chemical adsorption on modification diatomite. The adsorption of acetone, ethyl acetate, and toluene on Beta/Dt conformed to the pseudo-second-order kinetic model. In contrast, adsorption isotherms conformed to the Langmuir model, meaning that both physical and chemical adsorption occurred simultaneously during the adsorption process, and the adsorption belonged to the monolayer adsorption. The chemical adsorption mechanism can be ascribed to the nucleophilic reaction between the three VOCs (acetone, ethyl acetate, and toluene) and Beta/Dt with positive charges resulting from the modification diatomite. Furthermore, the composite could still keep more than 90% of the adsorption capacity of the original adsorbent after five regeneration cycles.

Two approaches are applied to outgoing longwave radiation (OLR) data to obtain abnormal changes before and after six earthquakes: the background field analysis (BFA) method, which focuses on statistically processing the increment of a radiation value to the multiyear average of the data; and the tidal force fluctuant analysis method, which abandons background data for many years by using the influence of tidal fluctuations to obtain incremental changes in radiation. The results demonstrate that the increase in OLR data identified via the BFA method was uncertain. In the time distribution, the occurrence time of anomalies is isolated and not continuous. In the spatial distribution, many OLR enhancement areas occurred multiple times in the nonseismic and remote seismic-related fault structure areas. In contrast, through the tidal force fluctuant analysis method a clear and consecutive OLR anomaly emerged in the seismogenic cycle of the tidal force. It corresponded with the tidal force through a unique evolution: increased-earthquake-shrink around the epicentre, consistent with the change in the law of thermal radiation during the rock-breaking process under stress, and clearly related to the earthquake's seismic tectonic stress change. It is proven that the tidal force of a celestial body may trigger an earthquake when the tectonic stress reaches its critical breaking point, and when the triggering action is a continuous rather than brief one-shot process. The in situ stress state is key. The OLR anomaly was the physical performance of underlying surface radiation from the change in seismic tectonic stress.

A magnetic composite based on TiO2 nanosheets, ZnFe2O4 and reduced graphene oxide (RGO) was synthesized by a one-step hydrothermal synthesis method, which possessed the band structure of a Z-scheme photocatalytic system. The properties and structures of the samples were characterized by XRD, UV-Vis DRS, Raman spectroscopy, SEM, EDS, XPS and PL spectroscopy. Compared with TiO2 nanosheets and the TiO2/RGO composite, the obtained ternary composite with 3 wt% RGO exhibited a significant enhancement in photocatalytic activities, attributed to the efficient charge separation induced by the fabricated Z-scheme system. About 99.7% of p-nitrophenol (p-NP) degraded within 60 min under simulated solar irradiation. Trapping experiments showed that superoxide anions (˙O2−) and hydroxyl radicals (˙OH) were the main active species in the p-NP photocatalytic degradation. Finally, a possible photocatalytic mechanism of Z-scheme ZnFe2O4/TiO2/RGO was proposed based on the results of trapping experiments and the energy bands of TiO2 and ZnFe2O4.

Snow is an important reservoir of volatile and semi-volatile organic compounds. In this paper, the adsorption kinetics and thermodynamics of gamma-hexachlorocyclohexane (γ-HCH) and other two kinds of important pollutants in the environment, 1,4-Dichlorobenzene (p-DCB) and trichloromethane (TCM), were investigated by the adsorption experiment. The results suggest that γ-HCH adsorption capacity on snow is much higher than that of p-DCB and TCM. The adsorption kinetics of the three pollutants fit the pseudo-second-order kinetic equation, and their adsorption thermodynamics accord with Henry's linear adsorption model. The effect of common inorganic salts (Na2SO4, Na2CO3 and NaNO3) on adsorption was positive, the presence of inorganic salts promoted the adsorption of γ-HCH, p-DCB and TCM on the snow. The adsorption of γ-HCH on natural snow was at least 3.5 times greater than that on artificial snow. All the results indicate that snow in cold regions may be the significant reservoir of organic pollutants.

In this study, we constructed MnO

Hexachlorocyclohexane (HCH), a typical organochloride pesticide, is one of the persistent organic pollutants. Despite the ban on technical grade HCH, it has been continuously observed at a steady level in the environment. The photochemical degradation of β-HCH in snow and ice under ultraviolet (UV) irradiation was investigated in this study. The effects of pH as well as common chemical components in snow on the degradation kinetics were investigated. In addition, the photodegradation products were determined and the reaction mechanism was hypothesized. The results showed that under UV irradiation, β-HCH can be photolyzed in snow and ice, with the photochemical degradation process conforming to the first-order kinetic equation. Changing the pH and adding Fe2+ had minimal effect on the photochemical degradation kinetics, while the presence of acetone, NO2-, NO3- and Fe3+ significantly inhibited the process. The addition of hydrogen peroxide slightly inhibited the photochemical degradation of β-HCH. Finally, the reaction rate, products and degradation mechanism of β-HCH in snow were compared with those in the ice phase. The photochemical degradation rate of β-HCH in snow was approximately 24 times faster than that in the ice phase. The photolysis product of β-HCH in snow was α-HCH, produced by the isomerization of β-HCH. However, in ice, in addition to α-HCH, pentachlorocyclohexene was produced by dechlorination. The results of this study are helpful in understanding the transformation of organochlorine pesticides in snow and ice, as well as in providing a theoretical basis for snow and ice pollution prevention and control.

Untreated livestock manure contains high concentrations of dissolved organic matter (DOM), which can enter the environment through leaching and eluviation, showing an important impact on the environment. In this research, fresh chicken manure from a large-scale chicken farm was collected as the source of DOM. The infrared spectrum of the original DOM was characterized. TOC analysis, UV spectrum and 3D fluorescence spectrum were used to measure the properties of DOM before and after photodegradation. Infrared spectroscopy results show that chicken manure DOM may contain aliphatic and aromatic compounds, alcohols, phenols, polysaccharides and some protein substances; In three systems, the order of TOC removal rates of DOM was water + UV system (85%) water + simulated sunlight system (7.2%) ice + simulated sunlight system (4.5%); Changes of UV spectra, fluorescence spectra, molecular weight distribution and pH value show that, in three systems, as the illumination time increased, photodegradation reduced pH value of the systems, aromaticity and humus contents of DOM, while increased the proportion of medium and/or small molecular weight components of DOM. The amounts of all these changes were proportional to DOM photodegradation rates in the system. The binding ability of DOM with Cu

In this study, heterojunction photocatalysts, XAg@C-TCZ, based on MOF-derived C-TiO

The present work compared electrocoagulation (EC)/pecan shell (PS) coupling process with a simple electrocoagulation (EC) process for the removal of tetracyclines (TCs). The results indicated that the addition of appropriate PS could lead to the enhancement of the removal efficiency and decrease of operating time via synergistic influence, including conventional EC process, biomass materials adsorption, charge neutralization and coordination adsorption. The ideal condition for the coupling process was 2.5 mA/cm2 for current density and 3 cm for plate spacing. Based on the optimum condition, when the dosage of PS was 5 g/L, the initial concentration of tetracycline hydrochloride (TC), oxytetracycline hydrochloride (OTC) and chlortetracycline hydrochloride (CTC) was 250 mg/L, the removal rate of PS was 55.90%, 45.10% and 14.98% higher than those of EC process after 40 min treatment. In addition, compared to conventional EC process, the unit energy demand (UED) decreased by 49.62%, 53.2 4% and 26.35% and the unit electrode material demand (UEMD) decreased by 49.80%, 85.65% and 44.37%, respectively, which means more energy conservation and environmental protection.

Nitrated polycyclic aromatic hydrocarbons (NPAHs) are derived from PAHs, which are ubiquitous in the aqueous and atmospheric environments, and whose mutagenicity and carcinogenicity are much higher than that of PAHs. Therefore, their environmental transformation has attracted a lot of attention. In the present study, direct and indirect UV photodegradation kinetics of two NPAHs (1-nitropyrene and 1,8-dinitropyrene) in snow were investigated. It was found that the kinetics followed the pseudo-first-order kinetics with the photochemical degradation rate 0.3773 h−1 for 48.98 nM 1-NP and 0.3653 h−1 for 41.00 nM 1,8-DNP. Photosensitizers (hydrogen peroxide and nitrate) promoted the photodegradation of NPAHs. Considering the lower temperature and less microorganisms in snow environment, the photodegradation can be a key factor in determining the fate of NPAHs in sunlit surface snow. To the best of our knowledge, this is the first report on the photodegradation of NPAHs in snow.

Using the air temperature data of the National Center for Environmental Prediction (NCEP), we compared multiple layers of air temperature differences before, during and after the Jiujiang earthquake, and explored its relationship with the additive tectonic stress caused by celestial tide-generating force (ATSCTF). The earthquake occurred at the 1 of 4 high phases of ATSCTF, while the temperature rise came from land surface to high sky. It indicated that the tide force could trigger an earthquake when the tectonic stress was in critical status, and the air temperature rise reflected the terra stress change modulated under the tidal force. During the shock period of ATSCTF, the distribution of air temperature changes both near land surfaces and upper multi-layers along the active fault zones showed a tectonic disturbance pattern of calm before earthquake, rise during earthquake, calm after earthquake as well as a heat distribution pattern of the surface air warmed by land, uplifted by heat flux, cooled and dissipated in the sky. The pattern of changes obeyed the rule of thermal rise of rocks broken under stress loading and the principle of atmospheric thermal dynamic diffusion in vertical. We argued that an earthquake may also be a reason for air temperature differences rather than a simple weather process. At the same time, the rise of air temperature was synchronized with the ATSCTF fluctuant, which showed that tidal force had a particular indicative significance for the identification of temperature anomaly on seismic faults. Because of the mechanical characteristics of the study of earthquake thermal anomalies, it could help to identify the earthquake thermal anomalies and the climatic thermal anomalies, and provided a clear time-indication for the choice of the background temperature in the seismic thermal anomaly recognition.

In this study, we constructed MnO2/organic acid (OA) systems using MnO2 colloid, the most reactive phase of Mn(IV), and two kinds of OA (oxalic acid and l -tartaric acid). We investigated the effect of OA on tetracycline (TC) degradation by MnO2. The results show that both OA obviously accelerate TC degradation by MnO2. Mn(III) formed during the reaction lead to the acceleration. Mn(III)-oxalate complex formed in oxalic acid system resulted in the lower degradation efficiency than that in l -tartaric acid system. The acceleration of oxalic acid was decreased when the concentration was more than 75 μM, and even completely disappeared with the concentration of 500 μM, owning to the fact that excess oxalic acid decreased the pH and some MnO2 was fast reduced to Mn2+ by oxalic acid and unable to react with TC. The impact of pH on TC degradation resulted from the influences of H+ on MnO2 redox potentials and TC deprotonation. And acidic conditions accelerated TC degradation. The addition of Mg2+, Ca2+, Fe3+ and Zn2+ exhibited an inhibitory effect in both systems for their occupying reactive sites on MnO2 surface and blocking the access of TC to MnO2. Similar intermediates in the two systems were detected, indicating a similar TC degradation mechanism including a series of reactions like dehydration, hydroxylation and oxidation. The MnO2/OA system provides an efficient treatment of TC in wastewater. And it is also noticeable that MnO2/OA system should also have an important effect on the fate of pollutants in environment, from our results.

TiO2 is considered as one of the most promising semiconductor photocatalysts used to degrade organic pollutants. Element doping has a good effect on improving the properties of TiO2. Herein, by using Rb2SO4, we explored the in situ synthesis of Ti-based TiO2 sheets with a thin film through a hydrothermal reaction. Then, the photocatalyst was successfully fabricated by calcination. All samples were characterized by FT-IR, XRD, SEM, XPS, PL and UV-vis DRS measurements. The results indicate that the S doping together with surface hydroxyl groups lead to the band gap narrowing. S and a trace amount of Rb element can enable the formation of uniform microspheres on the surface of the Ti plate and the major phase transformed from titanium to anatase. The band gap absorption extended from 400 nm to 600 nm. The photocatalytic properties were investigated by performing the degradation of methyl orange (MO) and 4-chlorophenol (4-CP) in the aqueous solutions under UV and simulated sunlight. In the series of TiO2 photocatalysts, Rb/S/TiO2-48 shows the best photocatalytic efficiency and good photocatalytic performance on recycling. Interestingly, when H2O2 was added to the MO aqueous solution, a synergistic effect of the TiO2 thin film and H2O2 on degrading the pollutant was observed.

Four earthquakes above magnitude 5.0 in Yunnan and Tibet, China occurred from 2010 to 2011. By calculating the tidal-force changes induced by celestial bodies in this region, we found that the earthquakes occurred when tidal-forces continuous?ly grew from low to peak levels and approached the maximum amplitude phase, which indicated a tidal-force that had a trigger or inducing effect of active tectonic earthquakes when the ground stress reached a critical point. At the same time analyzing the abnormal changes of outgoing longwave radiation (OLR), along with the tidal cycle, indicated that the regional distribution of the enhancement region of OLR anomalies was closely related to geologic structure, especially ac?tive faults. The OLR radiation anomaly evolved: an initial infrared rise, followed by an enhancement reaching peak, attenuation, and then a return to normal. The entire process was similar to changes observed in rock-breaking process under stress loads. Our investigation showed that the tidal-force changes caused by ce?lestial bodies could trigger an earthquake when tectonic stress reached its critical breaking point, and the OLR anomaly was the radiation signature of the change in seismic tectonic stress. Therefore, the method of combining measurements of the tidal-force changes induced by celestial bodies with those of thermal-anomaly changes has some practical value for detecting the precursor state of impending earthquakes.

In this study, heterojunction photocatalysts, XAg@C-TCZ, based on MOF-derived C–TiO2 and Cd0.5Zn0.5S decorated with Ag nanoparticles (Ag NPs) were successfully synthesized through hydrothermal and calcination methods. The catalytic effectiveness of XAg@C-TCZ was evaluated by simultaneous photocatalytic degradation of rhodamine B (RhB) and reduction of Cr(VI) under simulated sunlight irradiation. The presence of the Z-scheme heterojunction was demonstrated through trapping experiments, X-ray photoelectron spectroscopy (XPS), time-resolved photoluminescence (PL) investigations, and electron spin resonance (ESR) spectroscopy. With an initial RhB and Cr(VI) concentration of 7 mg L−1 and 5 mg L−1, the catalyst 10Ag@C-TCZ achieved a simultaneous removal of 95.2% and 95.5% within 120 min, respectively. With the same catalyst, the degradation rate of RhB was 2.75 times higher and the reduction rate of Cr(VI) was 9.3 times higher compared to pure Cd0.5Zn0.5S. Total organic carbon (TOC) analysis confirmed the extent of mineralization of RhB, while the reduction of Cr(VI) was corroborated by XPS. Compared to pure RhB and Cr(VI) solutions, the reaction rates are smaller in the solution containing both contaminants, which is attributed to the competition for ·O2−. 10Ag@C-TCZ also exhibited a stable catalytic performance in tap water and lake water. This work provides a new perspective on the construction of heterojunctions with doped MOF derivatives for the purification of complex pollutant systems.

A magnetic composite based on TiO

Untreated livestock manure contains high concentrations of dissolved organic matter (DOM), which can enter the environment through leaching and eluviation, showing an important impact on the environment. In this research, fresh chicken manure from a large-scale chicken farm was collected as the source of DOM. The infrared spectrum of the original DOM was characterized. TOC analysis, UV spectrum and 3D fluorescence spectrum were used to measure the properties of DOM before and after photodegradation. Infrared spectroscopy results show that chicken manure DOM may contain aliphatic and aromatic compounds, alcohols, phenols, polysaccharides and some protein substances; In three systems, the order of TOC removal rates of DOM was water + UV system (85%) > > water + simulated sunlight system (7.2%) > ice + simulated sunlight system (4.5%); Changes of UV spectra, fluorescence spectra, molecular weight distribution and pH value show that, in three systems, as the illumination time increased, photodegradation reduced pH value of the systems, aromaticity and humus contents of DOM, while increased the proportion of medium and/or small molecular weight components of DOM. The amounts of all these changes were proportional to DOM photodegradation rates in the system. The binding ability of DOM with Cu2+ and Zn2+ in water solution decreased significantly after the photodegradation.

Constructing heterojunction has been widely accepted as an effective method to improve photocatalytic activity. Herein, Bi2S3 modified NH2-UiO-66 composites were prepared by facile hydrothermal reactions. The as-prepared NH2-UiO-66/Bi2S3 hybrids enhanced Cr (VI) photoreduction under simulated sunlight, which is due to the efficient separation of charge carriers. UV–vis DRS confirms the expansion of light absorption in visible light region and PL spectra proves the excellent separation of electron-hole pairs. Influence factors on Cr (VI) reduction such as the amount of Bi2S3 in photocatalysts, initial solution pH and the presence of organic dyes were also explored. 30NUB exhibited the best reduction effect among the YNUB series and acidic condition is favorable for Cr (VI) reduction. It is worth mentioning that a mutual promotion on Cr (VI) removal and dye degradation was also realized in Cr (VI)/dye mixed solution.

In this work, the photoconversion of 1-chloronaphthalene (CN-1) and 2,3-dichlornaphthalene (CN-10) under the simulated sunlight had been studied. The results showed that the photoconversion of CN-1 and CN-10 obeyed the first-order kinetics model. NO2−, NO3−, Fe3+ and Fe2+ extensively present in natural water can accelerate CN-1 photoconversion via generating ·OH, which may induce indirect photooxidation of CN-1. The photoproducts were treated by the derivatization method and analyzed by GC-MS after being irradiated for 6 h. Ten products were characterized for CN-1 and CN-10, and there were six common products. On this basis, the photoconversion pathways of CN-10 and CN-1 were proposed, and both of them have a similar conversion mechanism.

The salinization–alkalization of soil is an increasing environmental problem and a limiting factor for plant growth and productivity. This paper studied the morphological and physiological response...

In this study, soil containing four different concentrations of salt was used to grow Leymus chinensis, which was sampled over 120 days between the beginning of spring and the end of fall. During this time, its physiological and morphological characteristics were analyzed. Maximal superoxide dismutase and betaine content were observed under moderate saline-alkaline stress treatment (A3), and with increasing saline-alkaline stress, there was a linear increase in the contents of Na+, proline, malondialdehyde (MDA), organic acids (OAs), catalase, peroxidase, soluble protein and total soluble sugar. However, the K+ content and the K+/Na+ ratio decreased significantly. Under saline-alkaline stress, the K+, betaine, OA and soluble protein levels in the leaves were higher than those in the rhizomes, whereas the proline, MDA, protective enzyme and total soluble sugar levels in the leaves were lower than those observed in the rhizomes. The node density varied with increases in saline-alkali stress, and each node index was maximal at A3. Under saline-alkali stress, the rhizome biomass, leaf biomass and root–shoot ratio first decreased and then increased, whereas the change in root biomass showed a contrary tendency, and the specific root length increased gradually. There was a significant correlation between the root–shoot ratio, specific root length, and the physiological indexes. These results show that under different degrees of saline-alkali stress, L. chinensis is likely to use a series of adaptive physiological and morphological responses; the physiological responses were primarily related to the allocation of biomass and energy, root length, and the allocation of biomass between the aboveground and belowground organs.

The cycle process of the tidal force of celestial body for Lushan M7.0 earthquake, occurred in Lushan county of Sichuan, China on April 20, 2013 was calculated. The earthquake occurred at the lowest point phase. It indicated that the type of seismogenic fault that the tide force acted on belonged to the thrust fault. According to the tidal cycle, the abnormal air temperature change was analyzed based on NCEP satellite data around the whole China before and after the earthquake. The result showed that the air temperature changed evidently with the tide force changing. In temporal, the change went through: initial air temperature rise → strength→ reaching abnormal peak→ gradually decline; in spatial, the abnormal area winded its way along the margin of the southern Qinghai-Tibet Plateau and went through: scattered→ conversion→ scattered procession. The procession was similar to the change procession of a rock breaking under the stress loading. This shows that the stress change of rock may cause the air temperature change in the atmosphere before and after earthquake. It indicated that the tidal force of celestial body could trigger the earthquake, when the tectonic stress reaches its critical broken point and the air temperature anomaly was proportional to the seismic tectonic stress change. It was useful to combine air temperature and tidal force in earthquake precursory.

TiO

The photochemistry of organic pollutants has received increasing attention in ice and snow. In this work, the photoconversion of gamma-hexachlorocyclohexane (γ-HCH) under UV irradiation was investigated in water, snow and ice. The photoconversion rate, products and mechanisms were inspected, and the effect of inorganic ions (NO 2 − , NO 3 − , HCO 3 − and Fe 2+ ) was discussed. The results showed that γ-HCH could be photoconverted in water, snow and ice, with the photoconversion rate being fastest in snow, and slowest in ice. All photoconversion could be described by the first-order kinetics model. In water, snow and ice, the common photoproducts of γ-HCH were alpha-hexachlorocyclohexane (α-HCH) and pentachlorocyclohexene. α-HCH was generated by a change in the bonding of a chlorine atom in γ-HCH; pentachlorocyclohexene was generated by the removal of a molecule of chlorine hydride from a molecule of γ-HCH. Different concentrations of NO 2 − , NO 3 − and HCO 3 − all inhibited the photoconversion of γ-HCH, and the inhibition effect decreased with increasing concentrations of NO 2 − and NO 3 − , but increased with the increasing concentrations of HCO 3 − . Different concentrations of Fe 2+ promoted the photoconversion of γ-HCH in water and ice, but had little effect in snow.

The photoconversion of 4-chlorophenol (4-CP) in a simulated sunlight-Fenton system was investigated in ice and aqueous solution. It was found that the hydroxyl radical ( OH) had an important effect on the photoconversion of 4-CP in both phases, but the effects of Cl−, S O 4 2 − , N O 3 − , and HC O 3 − were different. In aqueous solution, the photoconversion efficiency of 4-CP was proportional to the OH concentration, and hence, Cl− and HC O 3 − as OH scavengers prohibited the photoconversion; S O 4 2 − had little effect; N O 3 − promoted the process under certain conditions owing to OH being generated by the photolysis of N O 3 − . In ice, however, the photoconversion efficiency of 4-CP was not proportional to the concentration of OH. The photoconversion efficiency of 4-CP increased with increasing concentrations of all ions, although the OH remained almost constant, only increasing or decreasing slightly. This provides new evidence for the presence of a quasi-liquid layer (QLL). Hydroxylation products were detected in both phases. All photoproducts in aqueous solution contained only a single benzene ring, whereas in ice, dimers were also detected.

This paper presents a validation and confutation analysis using the methods of the robust satellite data analysis technique (RST) to detect seismic anomalies within the bi-angular Advanced Along-Track Scanning Radiometer (AATSR) data based on spatial/temporal continuity analysis. The distinguishing feature of our method is that we carried out a comparative analysis of seismic anomalies from bi-directional observation, which could help understanding seismic thermal infrared (TIR) anomalies. The proposed method has been applied to analyse bi-angular AATSR gridded brightness temperature data with longitude from 5 to 25° E and latitude from 35 to 50° N associated with the earthquake that occurred in Abruzzo, Italy, on 6 April 2009, and a full data set of 7 yr data from 2003 to 2009 during the months of March and April has been analysed for validation purposes. Unperturbed periods (March–April 2008) have been considered for confutation analysis. Combining with the tectonic explanation of spatial and temporal continuity of the abnormal phenomena, along with the analysed results, a number of anomalies could be associated with possible seismic activities, which follow the same time and space. Therefore, we conclude that the anomalies observed from 29 March 2009 to 5 April 2009, about eight days before the Abruzzo earthquake, could be earthquake anomalies.

At present, heavy metal pollution has become a major environmental problem, influencing the survival of human and other creatures. Developing heavy metal ion adsorbents, which are environment friendly, of low cost and good performance is one of the effective means to solve heavy metal pollution. Rich low-grade diatomite mineral, as raw material, was modified with calcium carbonate to improve the adsorption properties of diatomite for heavy metal ions. The effects of dosage(m), pH, adsorbing time(t), temperature(T) and concentration of adsorbent(c) on the removal rate of heavy metal ions(Cu2+, Pb2+, Zn2+ and Cd2+) were studied. The results show that under the suitable conditions, T=15 °C, c=1.5 mmol/L, m=10 g/L, t=60 min, in a weak acid environment, the removal effect of the four kinds of metal ions by modified diatomite is the best.

The paper presents a wavelet transform method to identify possible seismic brightness temperature anomalies that might be associated with the Yushu (Ms = 7.1) earthquake that occurred in Qinghai province of China on 14 April 2010. Daily infrared data from the Chinese geostationary meteorological satellite FY-2E were used for the period from 1 January 2010 to 31 December 2011 and the spatial region 28.1–38.1° N by 91.7–101.7° E. We find that the wavelet transform is an effective method to analyse time series which contain nonstationary power, and identify here anomalous power both in the time and frequency domain. The results show that, over the two years, the relative wavelet power spectrum (RWPS) showed anomalous RWPS variations in nine cases: two of these were followed by earthquakes; seven were not. One of the two RWPS anomalies that were followed by an earthquake was in the southern area of the epicentre of the Yushu earthquake, with the RWPS anomaly starting to appear around 29 March 2010, decreasing in the period before the earthquake, and completely gone by 14 April 2010. The Yushu earthquake was the only strong earthquake within the region and two-year time period chosen, so the abnormal change of RWPS during this time period was possibly associated with the Yushu earthquake.

The thermodynamic characteristics of heavy metals adsorbed onto urban soil and the relative adsorption mechanisms were studied by the batch experiment. The results show that there existed dynamic adsorption-desorption equilibrium processes of cationic and anionic ions of heavy metals onto urban soil, which may have an impact on the pH of the adsorption system. The amounts of heavy metals adsorbed onto urban soil increased with the increase of the equilibrium concentration, but their adsorption amounts were not the maximum adsorption amounts. The higher the pH was, the greater the adsorption capacity of the urban soil at the same equilibrium concentration was, and the adsorption amounts of heavy metals onto urban soil followed the order of Pb>Cu>Cd>Zn>Ni. There were coordination reaction, hydrolysis reaction, exchange reaction in the adsorption processes of heavy metals onto urban soil. With the increase of pH, the influencing degree of pH on the different reactions of heavy metals in the soil increased, meanwhile the effects of other physicochemical properties of soil on the adsorption of heavy metals were weakened.

Anomalies of multi-parameters (outgoing longwave radiation, surface latent heat flux, air temperature, relative humidity, and air pressure) before the 12 May 2008 Wenchuan Ms =8.0 earthquake were discussed in order to obtain the seismic precursors. Multi-parameter data were computed based on multi-year background data. The results indicated that these parameters had significant variations prior to this event. The anomaly of outgoing longwave radiation was observed firstly, which gives an early warning. Next were air temperature, relative humidity, and air pressure, which had quasi-simultaneous variations in the basin and the mountain region close to the epicenter. The last was surface latent heat flux, which happened the day before this event. The characteristics of the parameter variations for this event are similar to other earthquakes, which is demonstrated in some other publications. The variations can be attributed to solid earth degassing and chemical reactions in the atmosphere. Additionally, the emission of gases from solid earth into the atmosphere could be ascribed to the tectonic stress of the Wenchuan earthquake.

The photochemistry of para-chlorophenol (4-CP) was studied under simulated sunlight (λ > 300 nm) and UV irradiation by using a 125 W high-pressure mercury lamp with or without a hard glass as light source in an ice matrix. The experiments were carried out in a photochemical cold chamber reactor at −14 to −12 °C. The photoconversion rate, photoproducts and photoconversion mechanism of 4-CP were all inspected and compared. The results show that the 4-CP photoconversion obeys the first order kinetic model and its photoconversion rate is highly affected by the initial concentration of 4-CP, light intensity and water quality. It is found that the conversion rate of 4-CP under UV irradiation is higher than that under simulated sunlight irradiation. The intermediate products of 4-CP were characterized by GC-MS, HPLC-ESI-MS and HPLC techniques and the possible photoconversion mechanism was proposed accordingly. It is concluded that the mechanism and photoproducts of 4-CP photolysis in ice are different from those in water, and the photoproducts and photoconversion pathways of 4-CP in ice varied with different light sources.

The paper presents an analysis by using the methods of Eddy field calculation mean and wavelet maxima to detect seismic anomalies within the outgoing longwave radiation (OLR) data based on time and space. The distinguishing feature of the method of Eddy field calculation mean is that we can calculate "the total sum of the difference value" of "the measured value" between adjacent points, which could highlight the singularity within data. The identified singularities are further validated by wavelet maxima, which using wavelet transformations as data mining tools by computing the maxima that can be used to identify obvious anomalies within OLR data. The two methods has been applied to carry out a comparative analysis of OLR data associated with the earthquake recently occurred in Haiti on 12 January 2010. Combining with the tectonic explanation of spatial and temporal continuity of the abnormal phenomena, the analyzed results have indicated a number of singularities associated with the possible seismic anomalies of the earthquake and from the comparative experiments and analyses by using the two methods, which follow the same time and space, we conclude that the singularities observed from 19 to 24 December 2009 could be the earthquake precursor of Haiti earthquake.

The formation of imminent hydrochemical precursors of earthquakes is investigated by the simulation for water–rock reaction in a brittle aquifer. Sixty-one soaking experiments were carried out with granodiorite and trachyandesite grains of different sizes and three chemically-distinct waters for 6 to 168 h. The experimental data demonstrate that water–rock reaction can result in both measurable increases and decreases of ion concentrations in short times and that the extents of hydrochemical variations are controlled by the grain size, dissolution and secondary mineral precipitation, as well as the chemistry of the rock and groundwater. The results indicate that water–rock reactions in brittle aquifers and aquitards may be an important genetic mechanism of hydrochemical seismic precursors when the aquifers and aquitards are fractured in response to tectonic stress.

The photochemistry of para-chlorophenol (4-CP) under UV irradiation by using a 125-W high-pressure mercury lamp as light source with the presence of nitrite in a solid water ice matrix had been studied. The experiments were carried out in a photochemical cold chamber reactor at −14 to −12 °C. Each influence factor of the 4-CP photoconversion kinetics in the water ice was inspected. The results show that the 4-CP photoconversion obeys the first-order kinetics model and the initial concentration of 4-CP, the initial concentration of nitrite, pH value, light intensity, inorganic ions and the water quality all have significant influence on the photoconversion rate. In addition, nine intermediate products were characterized by GC–MS, HPLC–ESI-MS and HPLC techniques and the possible photoconversion mechanism was proposed accordingly. It is concluded that the mechanism and photoproducts of 4-CP photolysis in ice are changed due to the presence of NO 2 − .

Copper phthalocyanine was selected as the photosensitizer to sensitizer TiO2 in this experiment with furfural as the target pollutant. The composite catalysts(TiO2/CuPC) obtained showed a great activity under a xenon lamp. By experiments, the optimal preparation conditions of the composite catalysts were set as follows: the CuPC loading mass fraction was 1.5%, the mass fraction of acetylacetone was 0.3%, and the stirring time was 10 h. UV-Vis diffuse reflectance spectra, XRD, and BET were used to characterize the properties of the composite catalysts, which showed that after loading CuPC on TiO2, the composite catalyst retained the same crystal structure as pure TiO2 and the wavelength range of its absorption spectrum was broadened to 600–700 nm while its surface area was smaller than that of the pure TiO2. Under the optimal conditions, 20 mg/L furfural solution was degraded by nearly 90% and TOC by about 70%. When the catalyst was reused 6 times, the activity of the catalyst was still retained by about 75%

Depending on the China Earthquake Network Center (CENC) measurement, the Yutian M7.3 earthquake struck at 5:19 pm on 12 February 2014. It happened in the Altyn Tagh fault zone. The cycle process of the tidal force of the celestial body for the earthquake was calculated firstly in this paper. From the result, we found that the earthquake occurred at the low point phase. Meantime, the OLR (Outgoing Long-wave Radiation) change was analyzed based on NOAA satellite data around the time of the earthquake in the China area. The preliminary result shows that the OLR have changed with the tide force changing for the earthquake. In temporal, the change went through: Initial OLR rise→strength→reaching abnormal peak→attenuation→return to normal. In detail, the initial indication of anomaly was detected on 9 Feb (3 days before the main shock) and the maximum reaches the value of 11W/m2 northward from the epicenter. And the anomalous area of 10 Feb is closest to the epicenter. There are still many theoretical questions have to be answered. However, OLR have become one of parameters used for precursor studies and the OLR early anomalies appearance of earthquakes.

A modified spectrophotometric method has been developed for the determination of phenol in water. The method is based on the reaction between phenol, sodium nitroprusside and hydroxylamine hydrochloride in a buffer medium of pH 10.6–11.8. The linear dynamic range is 0.05–5.0 mg l −1 . The optimum determination wavelength is at 700 nm. The molar absorptivity is 1.23×10 4 mol l −1 cm −1 . The relative standard deviation of the standard solution of phenol is 1.3% ( n =10, C =0.5 mg l −1 ). The average recovery of water samples spiked with phenol of 2.0 mg l −1 is 98.8% ( n =10). The relative error of standard sample ( C =0.394±0.003 mg l −1 ) is 2.0%. F values of the statistical analysis show that there is no significant difference between the proposed method and the 4-aminoantipyrine method. The crystal of the product of the colored reaction was synthesized. According to its IR spectrum, Raman spectrum, Mossbauer spectrum and elemental analysis, the composition and structure of the product have been deduced and the mechanism of the colored reaction has also been investigated.