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A porous cobalt(ii) metal–organic framework (MOF) was reported to exhibit high room-temperature proton conduction and field-induced slow magnetic relaxation behavior.

Three new 2D MnII-[MoIII(CN)7]4− magnets constructed from chiral bidentate ligands have been synthesized and characterized. The relationship between the magnetic properties and the anisotropic magnetic interactions was analyzed and discussed.

A one-dimensional Dy(iii) sulfonate was reported to exhibit switched single-ion magnetism and proton conduction induced by water desorption/adsorption processes in a single-crystal-to-single-crystal transformation manner.

A dysprosium(iii) single-ion magnet (SIM) was used as a building block for the construction of dinuclear lanthanide single-molecule magnets (SMMs).

The supramolecular assembly of hexaaquacobalt(II) nitrate and a tetradentate carboxylate ligand resulted in the isolation of a cobalt hydrogen-bonded organic framework (HOF). Variable-temperature X-ray diffraction experiments reveal high thermal stability of the framework sustained by charge-assisted, multiple hydrogen bonding interactions with the co-former. Interestingly, the material shows field-induced slow relaxation of magnetization originating from the magnetically anisotropic Co

Spin crossover (SCO) complexes have been extensively explored as bistable materials and recently used as molecular modules for the development of new multifunctional molecular magnetic materials. Herein, we present the synthesis, crystal structure, magnetic, and electrical properties of a mononuclear cobalt complex constructed by a halogen-functionalized terpyridine derivative and organosulfonate. A complete and gradual spin transition with the T

Anisotropic magnetic exchange is of great value for the design of high performance molecular nanomagnets. In the present work, enhanced single-chain magnet (SCM) behavior is observed for a MoIII -MnII chain that exhibits anisotropic magnetic exchange. Self-assembly of the pentagonal bipyramidal [Mo(CN)7 ]4- anion and the MnII unit with a tridentate ligand results in a neutral double zigzag 2,4-ribbon structure which exhibits SCM behavior with a high relaxation barrier of 178(4) K. Open magnetic hysteresis loops are observed below 5.2 K, with a coercive field of 1.5 T at 2 K. Interestingly, this SCM can be considered to be a result of a step-wise process based on our previously reported Mn2 Mo single-molecule magnets (SMMs).

Field-induced slow magnetic relaxation was observed in two interpenetrated cobalt(II) metal–organic framework (MOF) isomers constructed from a dual-functional ligand 1H-benzimidazole-5-carboxylic acid, which represent the first example of MOF isomers showing field-induced single-ion magnet behavior.

Foldable displays have become increasingly used as a solution to the portability-practicality trade-off. A new scan driver integrated with metal oxide thin film transistors (MO TFTs) is proposed for foldable displays to overcome the effects of threshold voltage shifts on the scan driver output. In the scan driver, a feedback section and two series to transistor structures are used to keep the voltage of the key node to sustain a normal output, with this structure, the lower the voltage of the negative supply, the more stable the scan driver will be. Some flexible MO TFTs and 60 stage scan drivers are fabricated by etch stop layer structures on the polyimide substrate. Under different strains and 100 000 times bending with the minimum 3.5 mm bending radius, the characteristics of MO TFTs and the output waveform of the scan driver are measured. Experimental results show that the proposed scan driver shows high reliability since only a little voltage fluctuation occurs at the outputs after the bending test and has a better output waveform with a lower voltage of the negative supply.

BackgroundHepatocellular carcinoma (HCC) is the sixth most common cancer in the world and the third leading cause of cancer-related death. Although the diagnostic scheme of HCC is currently undergoing refinement, the prognosis of HCC is still not satisfactory. In addition to certain factors, such as tumor size and number and vascular invasion displayed on traditional imaging, some histopathological features and gene expression parameters are also important for the prognosis of HCC patients. However, most parameters are based on postoperative pathological examinations, which cannot help with preoperative decision-making. As a new field, radiomics extracts high-throughput imaging data from different types of images to build models and predict clinical outcomes noninvasively before surgery, rendering it a powerful aid for making personalized treatment decisions preoperatively.ObjectiveThis study reviewed the workflow of radiomics and the research progress on magnetic resonance imaging (MRI) radiomics in the diagnosis and treatment of HCC.MethodsA literature review was conducted by searching PubMed for search of relevant peer-reviewed articles published from May 2017 to June 2021.The search keywords included HCC, MRI, radiomics, deep learning, artificial intelligence, machine learning, neural network, texture analysis, diagnosis, histopathology, microvascular invasion, surgical resection, radiofrequency, recurrence, relapse, transarterial chemoembolization, targeted therapy, immunotherapy, therapeutic response, and prognosis.ResultsRadiomics features on MRI can be used as biomarkers to determine the differential diagnosis, histological grade, microvascular invasion status, gene expression status, local and systemic therapeutic responses, and prognosis of HCC patients.ConclusionRadiomics is a promising new imaging method. MRI radiomics has high application value in the diagnosis and treatment of HCC.

Reversible controlling and switching of magnetic bistability remains relatively difficult. Here, reversible on–off switching of a hysteretic spin transition in a CoII complex via a single-crystal t...

Thirteen typical antibiotics in surface water of the Lianhua Reservoir were analyzed using HPLC/MS/MS to assess the pollution characteristics and risk levels. Ten antibiotics except for erythromycin, sulfadiazine, and sulfamethoxazole were detected in surface water and the total concentration of antibiotics varied between non-detectable (n.d.) and 925.26 ng ·L

The porous carbonaceous precursor obtained from elutrilithe by adding pitch powder and solid SiO2 was employed for the first time in an in situ hydrothermal synthesis of LSX zeolite/AC composite. The synthesized samples were characterized by XRD, SEM, and N2 adsorption&ndash, desorption. The optimum conditions for the hydrothermal synthesis process were set as follows: gelling, aging, and crystallization. The time and temperature required for these steps were 24 h and 65 &deg, C, 12 h and 20 &deg, C, and 48 h and 65 &deg, C, respectively. The molar ratios were (Na2O + K2O)/Al3O2 = 7.7, K2O/(K2O + Na2O) = 3. The potential applicability test of the product showed high CO2 working capacity, excellent CO2/CH4 and CO2/N2 selectivity, and high phenol adsorption capacity. These results suggest that the resultant product has excellent potential value in industrial application.

We herein reported the syntheses, structures, and magnetic properties of three dinuclear heterometallic MIILnIII complexes, namely, [MIILnIII(H2L)(CH3OH)2(NO3)2](NO3)·S (M = Co, Ln = Dy, S = MeOH (1CoDy); M = Zn, Ln = Dy, S = MeOH (2ZnDy); M = Co, Ln = Y, S = MeNO2 (3CoY), H4L = 2,6-diacetylpyridine bis[2-(semicarbazono) propionylhydrazone]. Synthesized from the predesigned multidentate ligand H4L, which has two different coordination pockets (smaller N3O2 and larger N2O4 pockets) suitable for either a 3d or a 4f metal center, all these complexes have very similar structures, where the MII centers possess a pentagonal bipyramidal (PBP) geometry and the LnIII sites have a tetradecahedron geometry. Magnetic measurements on these compounds revealed the existence of weak ferromagnetic coupling between the Co2+ and Dy3+ centers and the field-induced slow magnetic relaxation of all three complexes. Furthermore, theoretical calculation on all these complexes indicates that although the change of the diamagnetic Zn2+ ion to the paramagnetic Co2+ ion only slightly modifies the local magnetic anisotropy of the Dy3+ ion, the weak Co-Dy magnetic interaction decreases the energy barrier. These compounds are the first systematic results of a heterometallic 3d-4f single-molecule magnet containing predesigned PBP 3d metal ions.

Nitrile rubber O-rings seals for packaging barrel was stored in China tropical marine atmosphere environments for 10 years, and then the sealing function of nitrile rubber O-ring was failed. By comparing the molecular structure, cross-link density, thermal decomposition, content of elements and chemical functional groups of the original nitrile rubber seals, the surface and interior of nitrile rubber seals storage for 10 years, a long-term natural failure mechanism was studied. The results showed that: the surface content of dibutyl phthalate and dibutyl sebacate, the surface carbonyl peak height and the surface content of oxygen element were higher than that in internal; the surface cross-link density was lower than that in internal but still higher than in original sample; and surface carbon- to-oxygen ratio were lower than that in internal and original sample. After aging for 10 years, the weight loss of plasticizer decreased, and the main chain content increased. It can be inferred that nitrile rubber mainly undergoes oxygen-absorbing cross-linking reaction to form carboxylic acids and esters, which is accompanied by the migration and enrichment of two plasticizers to the surface, causing reductions in elasticity and elasticity. The residual permanent compression set was lower than the design critical value, and the sealing function for the packaging barrel was lost, and a leak occurred.

By reaction of K4[MoIII(CN)7]·2H2O, Mn(ClO4)2·6H2O and bidentate chelating ligands, three new cyano-bridged compounds, namely Mn2(3-pypz)(H2O)(CH3CN)[Mo(CN)7] (1), Mn2(1-pypz)(H2O)(CH3CN)[Mo(CN)7] (2) and Mn2(pyim)(H2O)(CH3CN)[Mo(CN)7] (3) (3-pypz = 2-(1H-pyrazol-3-yl)pyridine, 1-pypz = 2-(1H-pyrazol-1-yl)pyridine, pyim = 2-(1H-imidazol-2-yl)pyridine), have been synthesized and characterized structurally and magnetically. Single crystal X-ray analyses revealed that although the chelating ligands are different, compounds 1 to 3 are isomorphous and crystallize in the same monoclinic space group C2/m. Connected by the bridging cyano groups, one crystallographically unique [Mo(CN)7]4- unit and three crystallographically unique MnII ions of different coordination environments form similar three-dimensional frameworks, which have a four-nodal 3,4,4,7-connecting topological net with a vertex symbol of {43}{44·62}2{410·611}. Magnetic measurements revealed that compounds 1-3 display long-range magnetic ordering with critical temperatures of 64, 66 and 62 K, respectively. These compounds are rare examples of a small number of chelating co-ligand coordinated [Mo(CN)7]4--based magnetic materials. Specifically, the bidentate chelating ligands were successfully introduced into the heptacyanomolybdate system for the first time.

By the reaction of H2valen, Cu(NO3)2·3H2O, LnCl3·6H2O and NaN(CN)2, three new heterometallic CuII–LnIII complexes, [(Cu(valen)La(NO3)(CH3OH)(dca)(μ-dca)]2 (1), [Cu(Cl)(valen)Ln(NO3)(CH3OH)(H2O)(dca)] [Ln = Tb (2), Dy (3)] [H2valen = 1,2-ethanediylbis(2-iminomethylene-6-methoxy-phenol); dca = dicyanamide], have been synthesized and characterized. The structure of complex 1CuLa is found to be a tetranuclear [CuLa]2 cluster with the La centre bridged by two dca ligands, while complexes 2CuTb and 3CuDy remain as isolated monomers with the dca molecules acting as terminal ligands. Direct current susceptibility investigations show ferromagnetic interactions between the Cu(II) and Tb(III) or Dy(III) ions in complexes 2CuTb and 3CuDy. Slow magnetic relaxation behaviour is observed in the complex 2CuTb, with an effective energy barrier Ueff of 21.85 K.

A bicomponent ion-pair molecule compound [Co(Brphterpy)₂][Co(NCS)₄]*2MeCN was designed and prepared for the construction of the functional materials of multi-stability. Due to the different coordination geometries of the cationic and anionic CoII ions, this compound exhibits both the thermally-induced spin crossover (SCO) and field-induced single-ion magnetism (SIM). This represents a rare example of a two-component system with the coexistence of SIM and SCO behaviors and suggests a simple, yet very efficient strategy for the construction of multi-stable molecular materials.

Crystal structures and magnetic properties of three one-dimensional (1D) azido-bridged cobalt(II) chains with different amide ligands (L), [Co2(N3)4(DMF)3] (1), [Co4(N3)8(DEF)5] (2), and [Co2(N3)4(DIPF)2] (3) (DMF = N,N-dimethylformamide, DEF = N,N-diethylformamide, and DIPF = N,N-diisopropylformamide), are reported to investigate the influence of L on their structures and magnetic properties. Single-crystal X-ray crystallographic analysis revealed that, although 1–3 all consist of cobalt chains bridged by end-on (EO) azides, the coordination geometry of the CoII ions and the repeating units of the 1D structures are quite different. As the size of L increases, the ratio of L to CoII decreases from 6:4 in 1 to 5:4 and 4:4 in 2 and 3, respectively. In 1, two [CoN5O1] and two [CoN4O2] distorted octahedra form the {[CoN5O1][CoN4O2]2[CoN5O1]} tetramers (denoted as Co4A), which are linked to each other by sharing the N–N edge to form the chain. Similarly, the chain structure of 3 is constructed from a similar t...

Two cyanide-bridged compounds based on the FeII cation and the anisotropic [MoIII(CN)7]4– anion, namely, {Fe2(H2O)5[Mo(CN)7]·5H2O}n (1) and {[NH2(CH3)2]2Fe5(H2O)10[Mo(CN)7]3·8H2O}n (2), have been prepared. Single crystal X-ray analyses revealed that their structures exhibit different three-dimensional topologies as a result of the addition of [NH2(CH3)2]+ during the synthesis of 2. For both 1 and 2, the geometry of the [Mo(CN)7]4– unit is a slightly distorted capped trigonal prism; all FeII centers are hexacoordinate and adopt a distorted octahedral configuration. Compound 1 is a three-nodal 3,4,7-connected net with the point symbol of {4.62}{45.6}{46.612.83}, while compound 2 is a five-nodal 4,4,4,6,7-connected net with the point symbol of {44.62}{45.6}4{46.67.82}{49.611.8}2. Magnetic studies revealed that both compounds exhibit magnetic ordering below 65 K. Apart from the plethora of MnII–[Mo(CN)7]4– compounds documented in the literature, these two FeII–[Mo(CN)7]4– compounds are the only other [Mo(CN)7...

Two seven-coordinate compounds with pentagonal bipyramidal YbIII centers, namely, [Yb(H3Bmshp)(DMF)2Cl2]·DMF·1.5H2O (1) and [Yb(H3Bmshp)(DMF)2Cl2]·H4Bmshp (2) (H4Bmshp = (2,6-bis[(3-methoxysalicylidene)hydrazinecarbonyl]-pyridine)) were synthesized by changing the molar ratio of reactants in DMF. The structures of compounds 1 and 2 are very similar, except for the existence of different lattice molecules: one DMF and one and a half water molecules in 1, and one neutral uncoordinated ligand in 2. The coordination geometries of both the pentagonal bipyramidal YbIII centers (YbCl2N1O4) in compounds 1 and 2 are also very similar with only slight differences. Magnetic data analyses revealed that the subtle structure variations result in remarkable different slow magnetic relaxation properties of compounds 1 and 2. To further understand their magnetic behaviors, ab initio calculations were performed for both compounds 1 and 2. The calculated results indicate that the magnetic anisotropies of compounds 1 and 2 are significantly different: easy-plane magnetic anisotropy for 1 and easy-axis magnetic anisotropy for 2. To the best of our knowledge, these compounds are the first YbIII-based SIMs of pentagonal bipyramidal geometry.

The rational design and synthesis of heptacyanomolybdate-based magnets remain a challenge due to the complexity of this system. Here, we reported the crystal structures and magnetic properties of two three-dimensional (3D) frameworks prepared from the self-assembly of the [Mo

Two rhodamine B-based compounds 1 and 2 were prepared for application of fluorescence Cr(III) probes, and they inherit aggregation induced emission (AIE) features with strong red emission in water. Fluorescence spectra and cell imaging proved that compounds 1 and 2 were highly responsive to Cr(III), and they were employed to investigate the decomposition of chromium picolinate (Cr(pic)3) in the living cells. As a result, Cr(III) was captured by compound 1 and 2 from Cr(pic)3 in living cell. This result demonstrated that the biological mechanism of Cr(pic)3 could be explored by the fluorescent tracer.

Objective:GJB2 gene mutations are highly prevalent in pre-lingual hearing loss patients from China. Pre-lingual deafness is a sensorineural disorder that can only be treated with cochlear implantation.Method:The prevalence of GJB2 gene mutations was examined in 330 randomly selected patients treated with cochlear implantation.Results:Overall, 276 patients (83.64 per cent) carried variations in the GJB2 gene. Seventeen different genotypes were identified, including 10 confirmed pathogenic mutations (c.235delC, c.299delAT, c.176del16, p.E47X, p.T123N, p.V167M, p.C218Y, p.T86R, p.V63L and p.R184Q), 3 polymorphisms (p.V27I, p.E114 G and p.I203 T) and 2 unidentified mutations (p.V37I and c.571 T > C).Conclusion:A total of 103 patients (31.2 per cent) carried 2 confirmed pathogenic mutations. The frequency of c.235delC was higher than that reported previously in the Jiangsu province. The two novel mutations identified, 69C > G and 501G > A, are likely to be polymorphisms.

Starting from the pentagonal bipyramidal single-ion magnet [Co(tdmmb)(H2O)2][BF4]2 and a series of linear bridging ligands of different lengths, three new cobalt(II) one-dimensional (1D) coordination polymers, [Co(tdmmb)(pyz)][BF4]2·CH3CN·H2O (1), [Co(tdmmb)(apy)][BF4]2·2CH3CN (2), and [Co(tdmmb)(bpe)][BF4]2·3CH3CN (3) (tdmmb = 1,3,10,12-tetramethyl-1,2,11,12-tetra-aza[3](2,6)pyridino[3](2,9)-1,10-phenanthrolinophan-2,10-diene) (pyz = pyrazine) (apy = 4-aminopyridine) (bpe = 1,2-di(4-pyridyl)ethane)), have been synthesized and characterized structurally and magnetically. Symmetric ligands pyz and bpe result in the nearly linear chains in 1 and 3, while the asymmetric ligand apy leads to the zig-zag chain in 2. As the length of the ligands increases, the intrachain Co⋯Co distance also increases, i.e. 7.56, 7.70, and 13.85 A for 1–3, respectively. Magnetic investigation revealed the gradual decrease in the magnetic interactions between the Co2+ ions from 1 to 3, along with the increase in the intrachain Co–Co distances. Due to the existence of the weak antiferromagnetic (AF) interaction, the SIM behavior of the starting material is surpressed in compounds 1 and 2, and they show a simple paramagnetic behavior. While for 3, field-induced slow magnetic relaxation was observed at a low temperature with an energy barrier of Ueff = 19 K. This observation suggests that the magnetic interaction between the Co2+ centers in 3 is negligible, consistent with the very long Co–Co distance in 3. These 1D compounds are rare chain compounds composed of metal centers with a nearly D5h symmetry. Notably, compound 3 is the second example of a 1D Co(II) chain compound displaying a SIM behaviour. These studies illustrated that the magnetic interaction between the SIMs can be used to tune slow magnetic relaxation.

We herein reported the syntheses, structures, and magnetic properties of three dinuclear heterometallic M

Some kinds of compound soil conditioners were made from zero-valent aluminium, sulfur and calcium hydroxide according to a certain weight proportion of those materials. And a soil-pot trial was conducted to test effects of using them on vegetable yield, contents of cadmium and plumbum in vegetable, and the available contents in soils. Results indicate that, on the basis of “Pollution soil + chemical fertilizer” (i.e., treatment of “PS+CF”), it would increase vegetable’s yield, and decrease the contents of cadmium and plumbum of vegetable, enhance soil’s pH, but reduce the available contents of Cd and Pb in soils to a certain extent by using those soil conditioners (i.e., treatment of “PS+CF+Al1”, “PS+CF+Al2”, “PS+CF+Al3” and “PS+CF+Al4”).Among them, the effects of treatment “PS+CF+Al4” were relatively the best, and has a good application prospect in the field of soils, which were suffered from the contaminated by heavy metals Cd or Pb.

We herein report the syntheses, crystal structures, and magnetic properties of two complexes based on the anisotropic pentagonal bipyramidal FeII starting material [Fe(LN3O2)]2+, namely [Fe(LN3O2)(H2O)2][MQ]2·H2O (1) and [Fe(LN3O2)(CN)][ABSA]·3H2O (2) (LN3O2 = 2,13-dimethyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]octadeca-1(18),2,12,14,16-pentaene; MQ− = methyl orange anion; ABSA− = 4-aminoazobenzene-4′-sulfonic anion). Compound 1 is a mononuclear material where the [Fe(LN3O2)(H2O)2]2+ cations form a one-dimensional (1D) chain by the hydrogen bonds between the bulky MQ− anions and the coordinated water molecules. With a slightly different anion, ABSA−, a cyano-bridged FeII chain is formed for compound 2. This chain has a similar structure as that in our recently reported compound [Fe(LN5)(CN)][BF4] (Chem. Commun., 2015, 51, 4360). However, compared with the reported result where the chains interact with each other through the π⋯π interactions, the chains in 2 are well isolated by the bulky ABSA− anions with the shortest interchain Fe⋯Fe distances around 12.0 A. Magnetic investigation on 1 reveals the easy-axis magnetic anisotropy of the mononuclear FeII centre (zero-field splitting parameter D = −3.7 cm−1), which leads to the field-induced slow magnetic relaxation. For compound 2, the Fe2+ spins are antiferromagnetically coupled through the cyano bridges with a coupling constant of J = −4.13(2) cm−1 with the Hamiltonian H = −J∑Si·Si+1. AC magnetic measurements revealed the pure single-chain magnetic (SCM) behaviour of these isolated chains with an effective energy barrier of 26.1(5) K. This system represents a good example showing that the structures and magnetic properties, such as field-induced single-ion magnets, SCMs, and SCM-based magnets, can be selectively prepared by anion modification.

Dynamic molecular crystals are of high interest due to their potential applications. Herein we report the reversible on–off switching of single-molecule magnet (SMM) behavior in a [Mo(CN)7]4– based molecular compound. Upon dehydration and rehydration, the trinuclear Mn2Mo molecule [Mn(L)(H2O)]2[Mo(CN)7]·2H2O (1) undergoes reversible crystal-to-crystal transformation to a hexanuclear Mn4Mo2 compound [Mn(L)(H2O)]2[Mn(L)]2[Mo(CN)7]2 (2). This structural transformation involves the breaking and reforming of coordination bonds which leads to significant changes in the color and magnetic properties. Compound 1 is an SMM with an energy barrier of 44.9 cm–1, whereas 2 behaves as a simple paramagnet despite its higher ground state spin value. The distortion of the pentagonal bipyramidal geometry of [Mo(CN)7]4– in 2 disrupts the anisotropic exchange interactions that lead to SMM behavior in 1.

Crystal structures and magnetic properties of three one-dimensional (1D) azido-bridged cobalt(II) chains with different amide ligands (L), [Co

Two cyanide-bridged compounds based on the Fe

An accurate and sensitive method has been developed for the determination of PCBs in water by gas chromatography coupled with mass spectrometry (GC/MS) with ionic liquid based headspace single-drop microextraction under ultrasound. The sample injection part of gas chromatographic instrument was modifed to avoid the ionic liquid leaking, selected 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MI[PF6]) as extracting agents. Experimental parameters influencing the extraction performance, such as desorption temperature, ultrasound extraction time, extraction temperature, ionic liquid headspace volume and salt effect, were optimized. Calibration curve was linear within the range of 10~300.0 μg/L, and the extraction recoveries with RSD values lower than 9.1% were from 77.6% to 103.3%. The limits of detections (LOD), calculated on the basis of signal-to-noise ratio of 3 (S/N=3), was in the range of 0.005~0.007 μg/L. This method is found to be simple, sensitive, little interferential and good specificity for the determination of trace PCBs in water. Real sea sample was successfully analyzed using this method.

Self-assembly of the [Mo(III)(CN)7](4-) anion and the Mn(II) unit with a macrocyclic ligand results in the first example of a one-dimensional (1D) chain compound based on the heptacyanomolybdate, [Mn(LN5C10)]2[Mo(CN)7]·2H2O (LN5C10 = 1,4,7,10,13-pentaazacyclopentadecane). Because of the existence of the interchain magnetic coupling, long-rang magnetic ordering was observed in this compound.

A method is formulated to model the properties of honeycomb paperboard based on Hilbert transform, In this method, there are no assumptions on the forms of the stiffness and damping properties, this method is truly nonparametric. An experiment system is set up to record the free response of the mass loaded honeycomb paperboard system, the experiment data are used to identify the stiffness and damping properties of honeycomb paperboard. The motion equation of mass loaded honeycomb paperboard system is formulated, the transmissibility curve is simulated, the comparison of the simulated curves and the experiment data indicates the model in this paper is accurate.

Based on the daily meteorological data of seven stations in Altay region, China, this study investigated the temporal ( seasonal, inter-annual and decadal) and spatial variations of drought by using composite index of meteorological drought, as well as trend analysis, M-K abrupt analysis, wavelet analysis and interpolation tools in ArcGIS. The results indicated that the composite index of meteorological drought could reflect the drought condition in Altay region well. Although the frequency and the covered area of both inter-annual and seasonal droughts presented decreasing trends in the recent 52 a, the drought was still serious when considering the annual drought. The frequencies of inter-annual and spring droughts had no abrupt changes, whereas the frequencies of inter-summer, autumn and winter droughts had abrupt changes during the past 52 a. A significant periodic trend was also observed for the frequencies of inter-annual and seasonal droughts. The distribution of frequency and covered area suggested that the conditions of drought were heavily serious in Qinghe County, moderately serious in Altay City, Fuyun County, Buerjin County and Fuhai County, and slightly serious in Habahe County and Jimunai County.

Tetracycline antibiotics (TCs) such as doxycycline (DOTC), chlortetracycline (CTC), oxytetracycline (OTC), and tetracycline (TC) react with Cu(II) in pH 3.5 BR buffer medium to form 1:1 cationic chelates, which further react with titan yellow to form 2:1 ion association complexes. These result in great enhancement of resonance Rayleigh scattering (RRS) and the appearance of new RRS spectra. The ion association complexes of DOTC, CTC, OTC, and TC have similar spectral characteristics and their maximum RRS wavelengths are all located at 464 nm. The quantitative determination ranges and the detection limits (3sigma) of the four TCs are 0.037-4.8 microg mL(-1) and 11.2 ng mL(-1) for DOTC, 0.041-5.2 microg mL(-1) and 12.4 ng mL(-1) for CTC, 0.050-4.8 microg mL(-1) and 15.1 ng mL(-1) for TC, and 0.088-5.0 microg mL(-1) and 26.3 ng mL(-1) for OTC, respectively. The optimum reaction conditions, the effects of foreign substances, the structure of ternary complexes, and the reaction mechanism are discussed. A sensitive, rapid, and simple RRS method for the determination of DOTC has been developed.

In this work, the decolorization of azo dye Orange G (OG) in aqueous solution by aluminum powder enhanced by ultrasonic irradiation (AlP-UI) was investigated. The effects of various operating operational parameters such as the initial pH, initial OG concentration, AlP dosage, ultrasound power and added hydrogen peroxide (H2O2) concentration were studied. The results showed that the decolorization rate was enhanced when the aqueous OG was irradiated simultaneously by ultrasound in the AlP-acid systems. The decolorization rate decreased with the increase of both initial pH values of 2.0–4.0 and OG initial concentrations of 10–80 mg/L, increased with the ultrasound power enhancing from 500 to 900 W. An optimum value was reached at 2.0 g/L of the AlP dosage in the range of 0.5–2.5 g/L. The decolorization rate enhanced significantly by the addition of hydrogen peroxide in the range of 10–100 mM to AlP-UI system reached an optimum value of 0.1491 min−1. The decolorization of OG appears to involve primarily oxidative steps, the cleavage of N N bond, which were verificated by the intermediate products of OG under the optimal tested degradation system, aniline and 1-amino-2-naphthol-6,8-disulfonate detected by the LC–MS.