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Secondary soil salinization causes plant stress, which can be relieved by different ratios of red to far-red light (R:FR). Our study aimed to elucidate the role of low R:FR ratios treatments on photosynthesis and growth of tomato seedlings in salinized soils. Tomato seedlings were treated under three R:FR ratios and calcium nitrate was applied simultaneously. The results showed that the treatments under low R:FR ratios stimulated growth parameters of tomato seedlings under calcium nitrate stress, the best impact being achieved at the R:FR ratio of 0.7 in this experiment. Low R:FR ratios treatments increased proline content as well as PSII maximum efficiency, actual electron transport operating efficiency, and photochemical quenching of tomato seedlings under calcium nitrate stress but decreased the value of nonphotochemical quenching. Moreover, low R:FR ratios treatments promoted net photosynthetic rate and increased the expression of a Rubisco gene. In conclusion, low R:FR ratios treatments could improve the salt resistance of greenhouse tomato plants.

Mimicking enzyme specificity via construction of on-demand geometric structures on nanozymes is of great interest in recent years. Although building substrate-specific polymers on nanozymes has achieved great success, polymer-blocked active sites would inevitably lead to decreased activity of nanozymes. Here, we have developed three photoactive metal-organic framework (MOF)-based nanozymes (called 2D-TCPP, 3D-TCPP, and AD-TCPP), which have different geometric structures as well as unshielded active sites. Together with their structural variations and excellent photoresponsive oxidase-like activities, these photoactive nanozymes exhibit structure-dependent specificity for three kinds of substrates (typical oxidase substrates, organic pollutants, and antioxidants). Moreover, AD-TCPP and 3D-TCPP show potential applications for environmental protection and bioanalysis, respectively. This work offers a promising approach to the development of nanozymes with enzyme-like specificity.

Ceria (CeO2) nanozymes have drawn much attention in recent years due to their unique physiochemical properties and excellent biocompatibility. It is therefore very important to establish a simple and robust guideline to regulate CeO2 with desired multi-enzyme-mimicking activities that are ideal for practical bioapplications. In this work, the multi-enzyme-mimicking activities of CeO2 were regulated in a facile manner by a wet-chemical method with different synthesis temperatures. Interestingly, a distinct response in multi-enzyme-mimicking activities of CeO2 was observed towards different synthesis temperatures. And the regulation was ascribed to the comprehensive effect of the oxygen species, size, and self-restoring abilities of CeO2. This study demonstrates that high-performance CeO2 can be rationally designed by a specific synthesis temperature, and the guidelines from radar chart analysis established here can advance the biomedical applications of ceria-based nanozymes.

Analyzing the SOD-like activity of nanozymes in vitro is of great importance for identifying new nanozymes and predicting their potential biological effects in vivo. However, false negative or positive results occasionally occur due to the mismatch between the detection methods and nanozymes. Here, five typical SOD-like nanozymes, including CeO2, Mn3O4, Prussian blue (PB), PCN222-Mn, and Pt NPs, have been used to evaluate the sensitivity and accuracy of several commonly used in vitro detection methods. By systematically analyzing the detection results, several precautions have been taken. (1) The hydroethidine (HE) probe could be disturbed by the nanozyme with oxidative ability. (2) The nitro blue tetrazolium (NBT) probe has a moderate sensitivity due to the poor water solubility of its reduced product. (3) The water-soluble tetrazolium salt (WST)-8 probe has a higher sensitivity than both NBT and iodonitrotetrazolium chloride (INT). (4) The detection system using the irradiation of riboflavin to produce ˙O2− might be interfered by the nanozyme with photosensibility. (5) Both the quality of DMPO and incubation time are important factors for electron paramagnetic resonance (EPR) measurement. This study will be useful for choosing more suitable in vitro detection methods of SOD-like activity for nanozymes in the future.

BackgroundEnsete glaucum (2n = 2x = 18) is a giant herbaceous monocotyledonous plant in the small Musaceae family along with banana (Musa). A high-quality reference genome sequence of E. glaucum offers a vital genomic resource for functional and evolutionary studies of Ensete, the Musaceae, and more widely in the Zingiberales.FindingsUsing a combination of Illumina and Oxford Nanopore Technologies (ONT) sequencing, genome-wide chromosome conformation capture (Hi-C), and RNA survey sequence, we report a high-quality assembly of the 481.5Mb genome with 9 pseudochromosomes and 36,836 genes (BUSCO 94.7%). A total of 55% of the genome is composed of repetitive sequences with LTR-retroelements (37%) and DNA transposons (7%) predominant. The 5S and 45S rDNA were each present at one locus, and the 5S rDNA had an exceptionally long monomer length of c.1,056 bp, contrasting with the c. 450 bp monomer at multiple loci in Musa. A tandemly repeated c. 134 bp satellite, 1.1% of the genome (with no similar sequence in Musa), was present around all nine centromeres, with a LINE retroelement also found at Musa centromeres. The assembly, including centromeric positions, enabled us to characterize in detail the chromosomal rearrangements occurring between the x = 9 species and x = 11 species of Musa. Only one chromosome has the same gene content as M. acuminata (ma). Three ma chromosomes represent part of only one E. glaucum (eg) chromosome, while the remaining seven ma chromosomes are fusions of parts of two, three, or four eg chromosomes, demonstrating complex and multiple evolutionary rearrangements in the change between x = 9 and x = 11.ConclusionsThe advance towards a Musaceae pangenome including E. glaucum, tolerant of extreme environments, makes a complete set of gene alleles available for crop breeding and understanding environmental responses. The chromosome-scale genome assembly show how chromosome number evolves, and features of the rapid evolution of repetitive sequences.

Genome-wide association studies (GWASs) have identified dozens of genetic susceptibility loci for Alzheimer’s disease (AD). Nevertheless, the underlying causal variants and biological mechanisms remain elusive. Here, we systematically integrated AD GWAS with comprehensive multi-omics data, and distilled 304 potentially functional variants and 166 causal genes from 49 loci. Intriguingly, we found that most of AD GWAS loci contain multiple functional variants and causal genes. In vitro assays showed that one functional variant regulated multiple genes in the 11p11.2 locus (the CELF1/SPI1 locus) and alteration of these target genes contributed to AD-related molecular processes, supporting the co-existence of multiple functional variants and AD-relevant causal genes within a single locus. We thus proposed a multiple-causal-gene-cluster model that co-dysregulation of a cluster of genes within a single GWAS loci individually or synergistically contribute to AD development. This model provides a novel insight into the biological mechanisms underlying the GWAS loci of complex traits.

Nanozyme is a collection of nanomaterials with enzyme-like activity but exhibits higher environmental tolerance and long-term stability than their natural counterparts. Improving the catalytic activity and expanding the category of nanozymes are prerequisites to complement or even supersede natural enzymes. Specifically, a powerful hydrolytic nanozyme is demanded to degrade the unsustainable substance which natural enzymes hardly achieve. However, the development of hydrolytic nanozymes is still hindered by diverse hydrolytic substrates and following complicated mechanisms. Here, we apply two strategies which are informed by data to screen and predict catalytic active sites of MOF (metal–organic framework) based hydrolytic nanozymes. One is to increase the intrinsic activity by finely tuned Lewis acidity of the metal clusters. The other is to adjust the volume density of the active sites by shortening the length of ligands. Finally, we construct a Ce-FMA-MOF-based hydrolytic nanozyme with robust cleavage ability towards phosphate bonds, amide bonds, glycosidic bonds whose energy ascend in order; and even their mixture, biofilms. This work provides a rational methodology to design hydrolytic nanozyme, enriches the diversity of nanozymes, and potentially sheds a light on the evolution of enzyme engineering in the future.

We designed a cascade nanozyme with both superoxide dismutase– and catalase-mimicking activities for anti-inflammation therapy., Here, an integrated cascade nanozyme with a formulation of Pt@PCN222-Mn is developed to eliminate excessive reactive oxygen species (ROS). This nanozyme mimics superoxide dismutase by incorporation of a Mn–[5,10,15,20-tetrakis(4-carboxyphenyl)porphyrinato]–based metal-organic framework compound capable of transforming oxygen radicals to hydrogen peroxide. The second mimicked functionality is that of catalase by incorporation of Pt nanoparticles, which catalyze hydrogen peroxide disproportionation to water and oxygen. Both in vitro and in vivo experimental measurements reveal the synergistic ROS-scavenging capacity of such an integrated cascade nanozyme. Two forms of inflammatory bowel disease (IBD; i.e., ulcerative colitis and Crohn’s disease) can be effectively relieved by treatment with the cascade nanozyme. This study not only provides a new method for constructing enzyme-like cascade systems but also illustrates their efficient therapeutic promise in the treatment of in vivo IBDs.

SUMMARYWe investigated whether visuoauditory association can be artificially implanted in rodents and then retrieved in a behaviorally relevant context. Rats were trained to approach the left or right hole of a behavioral apparatus to retrieve a reward depending on the side of electrical stimulation of the auditory cortex (EAC) they received and mice were fear-conditioned to EAC. Next, an irrelevant visual stimulus (VS) was repeatedly paired with EAC in the presence of cholecystokinin (CCK) or with activation of terminals of entorhinal CCK neurons in the auditory cortex. In subsequent behavioral testing with VS, rats approached the hole associated with reward availability and mice showed a freezing response to the VS. A CCK antagonist blocked the establishment of visuoauditory association, whereas a CCK agonist rescued the deficit of association. Our findings provide a scientific foundation for “memory implantation” and indicate that CCK is the switching chemical for formation of visuoauditory association.

In order to understand the resource status and utilize the resources of Lilium cernuum, we have investigated the habitat, associated plants, populations and morphological characters of L. cernuum in Linjiang City, Baishan Prefecture, Jilin Province and Kuandian County, Dandong Prefecture, Liaoning Province of China. Wild bulbs of L. cernuum from Wohu Mountain, Linjiang City were introduced and cultivated in Beijing. The results indicated that the L. cernuum is distributed in all the investigated sites including Dianshita Mountain, Dahu Mountain and Zhenzhu Villa in Linjiang, and Dapushi River, Huabo Mountain and Xiaohu River in Kuandian. L. cernuum had strong adaptability and diversified habitats such as glade, forest understory, roadside shrub, ridge and cliff. There were rich associated plants including Quercus mongolica, Lespedeza bicolor, Atractylodes japonica and Fraxinus chinensis in both Linjiang and Kuandian. The native Linjiang population was stable while that of Kuandian was increasing type. There are some morphological differences between populations in Linjiang and Kuandian. Plants in the Linjiang population had higher stem of 44-70 cm and 34-53 leaves with 10-12 cm length and 1.80-1.82 mm wide. In the Kuandian population, plants had lower stem of 32-65 cm, 33-66 leaves with 10-13 cm length and 1.79-1.84 mm wide. There were 1-3 flowers in the raceme inflorescences which first flowering on July 10th 2012 in Linjiang, and 1-2 flowers in the raceme or umbel inflorescences that first opened on July 3rd 2013 in Kuandian. Fifty-nine plants emerged from 170 wild bulbs planted in Lvgezhuang Village, Changping District, Beijing on May 23, 2012 with the survival rate 34.7%. Under introduction conditions, the average stem height was 52 cm, leaves number is 48, with average 8 cm length and 2.08 mm wide. Although the stem height was not changed, leaf was 4 cm shorter and 0.2 mm wider than that in the original site. Nineteen flowers opened on June 16, 2013, 15 days earlier than the flowering in natural population with the flowering rate 11.2%. The individual flower bloomed for 3-4 days, and the whole population was flowering 21 days. We assume that temperature might be the key factor affecting the flowering, which contributes to an excellent prospect of commercialization of flower industry. This research provided the germplasm basis for the industrialization of wild lilies in China.

Hypertension is a typical example of long-term disease posing formidable challenges to health care. One goal of antihypertensive therapy is to achieve optimal blood pressure (BP) control and reduce co-occurring chronic conditions (multimorbidity). This study aimed to assess the influence of multimorbidity on medication adherence, and to explore the association between poor BP control and multimorbidity, with implications for hypertension management.\ud \ud A cross-sectional design with multistage sampling was adopted to recruit Chinese hypertensive patients attending general out-patient clinics from 3 geographic regions in Hong Kong. A modified systemic sampling methodology with 1 patient as a sampling unit was used to recruit consecutive samples in each general out-patient clinic. Data were collected by face-to-face interviews using a standardized protocol. Poor BP control was defined as having systolic BP/diastolic BP ≥130/80 mm Hg for those with diabetes or chronic kidney disease; and ≥140/90 mm Hg for others. Medication adherence was assessed by a validated Chinese version of the Morisky Medication Adherence Scale. A simple unweighted enumeration was adopted to measure the combinations of coexisting long-term conditions. Binary logistic regression analysis was conducted with medication adherence and multimorbidity as outcome variables, respectively, after controlling for effects of patient-level covariates.\ud \ud The prevalence of multimorbidity was 47.4% (95% confidence interval [CI] 45.4%–49.4%) among a total of 2445 hypertensive patients. The proportion of subjects having 0, 1, and ≥2 additional long-term conditions was 52.6%, 29.1%, and 18.3%, respectively. The overall rate of poor adherence to medication was 46.6%, whereas the rate of suboptimal BP control was 48.7%. Albeit the influence of multimorbidity on medication adherence was not found to be statistically significant, patients with poorly controlled BP were more likely to have multimorbidity (adjusted odds ratio 2.07, 95% CI 1.70–2.53, P < 0.001). Diabetes was the most prevalent concomitant long-term condition among hypertensive patients with poor BP control (38.6%, 95% CI 35.8–41.4 vs 19.7%, 95% CI 17.5–21.9 for patients with good BP control, P < 0.001).\ud \ud Multimorbidity was common among hypertensive patients, and was associated with poor BP control. Subjects with coexisting diabetes, heart disease, or chronic kidney disorder should receive more clinical attention to achieve better clinical outcomes.

Preliminary progress is reported in this communication in building a planar anode-supported low-temperature solid oxide fuel cell (SOFC) stack based on gadolinia-doped ceria (GDC) electrolyte, i.e. fabrication and characterization of a Ø80 planar bilayer structure composed of GDC electrolyte film and Ni–GDC anode substrate. The anode substrates were prepared from mixtures of NiO, GDC, and carbon black by die-pressing. After pre-firing to remove the carbon black, the anode substrates were deposited with a GDC layer using a spray coating technique. The green bilayers of anode substrate and electrolyte film were then co-sintered at 1500 °C for 3 h. Through proper control of the sintering process, bilayer structures with excellent flatness were achieved after co-sintering. Scanning electron microscopy (SEM) observation indicated that the electrolyte film was about 22 μm in thickness, highly dense, crack-free, and well-bonded to the anode substrate. Small disks which were cut out from the Ø80 bilayer structure were electrochemically examined in a single button-cell mode incorporating a (LaSr)(CoFe)O3–GDC composite cathode. With humidified hydrogen as the fuel and air as the oxidant, the cell demonstrated an open-circuit voltage of 0.884 V and a maximum power density of 562 mW/cm2 at 600 °C. The results imply that high-quality anode-supported electrolyte/anode bilayer structures were successfully fabricated. Based on them, planar anode-supported SOFC stacks will be assembled in the future. Keywords: Solid oxide fuel cell, Stack, Anode-supported SOFC, GDC electrolyte, Thin film, Co-sintering

Juglans regia L. is an important nut fruit, but our basic knowledge of it still lags behind that of other plants. In this study, the ultrastructure of the fleshy pericarp and seed coat cells was systematically investigated using transmission electron microscopy during the entire developmental process of the fruit. Our observations showed that during the early stage of fruit development mesocarp cells display the primary characteristics of immature cells, namely numerous organelles, an extensive distribution of plasmodesmata, and the presence of starch grains. As the fruit develops, the vacuole, vesicles and intercellular spaces clearly enlarge, organelles begin to degrade and, at a later stage, phenol grains appear. Although there are no plasmodesmata in the endocarp there is a complex cytoarchitecture in the episperm of the developing seed, with many phenolic substance granules. The mesosperm contains an electron-dense protoplasm with a thin cell wall, enriched with organelles, and has numerous plasmodesmata, although there are almost no starch grains. The companion cells (CCs) are enriched with mitochondria, and the sieve elements (SEs) contain many vesicles in the SE–CC complex of the mesosperm, from which the sieve plate of the SE is built up. The endotesta cells, which are large and loose, form a nourishment-free diffusion space. There is complex vesicle movement in the fleshy pericarp and seed coat. Based on structural and diagnostic changes within the fleshy pericarp and seed coat, the cytological characteristics of substance transport in the walnut fruit are discussed. The main conclusion is that fleshy pericarp parenchyma cells are the nutrient bank, while the parenchyma tissue of the seed coat is the transfer station that transports nutrients to the embryo. Vesicle transportation is the third method of transportation of materials between cells and the transfer cell of the walnut seed coat is characterized by a multitude of mitochondria. This study makes a significant contribution to our understanding of ultracellular events in the developing walnut fruit.

A high-performance, cathode-supported solid oxide fuel cell (SOFC), suitable for operating in weakly humidified hydrogen and methane, has been developed. The SOFC is essentially made up of a YSZ–LSM composite supporting cathode, a thin YSZ film electrolyte, and a GDC-impregnated La 0.75 Sr 0.25 Cr 0.5 Mn 0.5 O 3 (LSCM) anode. A gas-tight thin YSZ film (27 μm) was formed during the co-sintering of the cathode/electrolyte bilayer at 1200°C. The cathode-supported SOFC developed in this study showed encouraging performance with maximum power density of 0.182, 0.419, 0.628 and 0.818 W/cm 2 in air/3% H 2 O–97% H 2 (and 0.06, 0.158, 0.221 and 0.352 W/cm 2 in air/3% H 2 O–97% CH 4 ) at 750, 800, 850 and 900°C, respectively. Such performance is close to that of the cathode-supported cell (0.42 W/cm 2 versus 0.455 W/cm 2 in humidified H 2 at 800°C) developed by Yamahara et al. [1] [DOI: 10.1016/j.ssi.2004.09.023] with a Co-infiltrated supporting LSM-YSZ cathode, an (Sc 2 O 3 ) 0.1 (Y 2 O 3 ) 0.01 (ZrO 2 ) 0.89 (SYSZ) electrolyte of 15 μm thickness and an SYSZ/Ni anode, indicating that the performance of the GDC-impregnated LSCM anode is comparable to that made of Ni cermet while stable in weakly humidified methane fuel.

Attenuation of the coherent and scattered surface-wave noise for land seismic data is very critical to the data processing to produce high-resolution images and to extract reliable seismic attributes for the reservoir characterization. Conventional noise attenuation methods are usually not effective to remove the aliased components of coherent noise and also not effective to address the apices of the scattered surface waves. Here we present the application of a new model-based surface wave attenuation technique that is based on data-driven modeling of multiple modes of aliased direct and diffracted noise for the seismic data from Sulige tight sand gas reservoir in China. The surface consistent propagation properties of the surface waves are estimated first. The direct noise is modeled and then the scattering model is built by the integration of all possible diffractors. All of the noise models are finally subtracted from the raw data. In this paper, we demonstrate a successful case study how this new technology can be used to help the improvement of the signal to noise ratio and the fidelity of seismic data with the finest resolution and sufficient amplitude preservation.

A traveling wave ultrasonic motor of high torque with a new configuration is proposed in this paper. In the new design, a part of the motor serves as the stator. The rotor is the vibrator consisting of a toothed metal ring with piezoelectric ceramic bonded, which generates ultrasonic vibration. The rotor is in contact with the shell of motor and is driven by the friction between the rotor and the stator. This configuration not only removes the rotor in a conventional type of traveling wave ultrasonic motor but also changes the interaction between the rotor and the stator of the motor so that it improves the output performance of the motor. Although an electric brush is added to the ultrasonic motor, it is easy to be fabricated because of the low speed of motor. The finite element method was used to compute the vibration modes of an ultrasonic motor with a diameter of 100 mm to optimize the design of the motor. A 9th mode was chosen as the operation mode with a resonance frequency about 25 kHz. According to the design, a prototype was fabricated. Its performance was measured. The rotation speed–torque curves for various frequencies were obtained. The result shows that its stall torque is greater than 4 N m within a range of 400 Hz. This ultrasonic motor was used to drive the window glass of a mobile car and the result was satisfactory. In the further the research on the friction material between the stator and the rotor is under way to improve the efficiency of the ultrasonic motor.

Two serials of Eu3+ doped AlN films are prepared by means of magnetron RF reactive sputtering under different RF powers and N-2/(N-2 + Ar) ratios. XRD analysis indicates that the films change from amorphous to c-axis oriented crystalline as the RF power increases or as the N-2/(N-2 + Ar) ratio decreases. Lower N-2/(N-2 + Ar) ratio and higher RF power enhance the deposition rate and crystallinity. The grain size and surface roughness observed by SEM and AFM increase with the increase of the RF power. The emission from 5 Do to F-7(J) (J = 0-4) of Eu3+ is observed in the PL spectra for all the crystalline films, and the D-5(0) to F-7(2) transition of the films grown at 300 W has double exponential decays, 38 and 161 mu s. The crystalline quality of the films improves the photoluminescence intensity. (C) 2005 Elsevier B.V. All rights reserved.

A serial of samples in Y2O3-Ga2O3-Tm2O3 pseudo-ternary system are prepared by solid-state chemical reaction method. The range of solid solution in (Y1-xTmx)(3)GaO6 is 0 F-3(4) transition at room temperatures with two lifetimes (similar to 5 and similar to 15 mu s) and a narrow saturation range of PL intensity for the Tm3+ content from x = 0.005 to 0.03. The sharp emission and long lifetime of (Y1-xTmx)(3)GaO6 indicate that Y3GaO6 is a potential phosphor and laser crystal host material. (c) 2005 Elsevier Inc. All rights reserved.

Ln(3+) (Ln = Nd, Sm, Eu, Gd, Dy, Ho, Er)-doped Y3GaO6 compounds were prepared by solid-state reaction, and their optical spectra such as absorption, photoluminescence, excitation and time-resolved spectra have been measured for Ln Nd, Sm, Dy, Ho, Er. X-ray powder diffraction shows that the lattice parameters of the compounds (Y(0.96)Ln(0.04))(3)GaO6 decrease with the decrease of the radii of trivalent Ln(3+) ions, indicating that Ln(3+) ions have substituted for y(3+) ions in the lattice. Optical spectra show that there are obvious absorptions at ultraviolet to visible region. The strong emissions in visible and infra-red region show that Y3GaO6 is a suitable host for rare-earth-doped laser crystal and phosphor materials. (C) 2004 Elsevier B.V. All rights reserved.

The crystal structures of a series of compounds with the composition Ln(3)GaO(6)(Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho and Er) synthesized by solid-state reaction at 1400degreesC are investigated. X-ray diffraction shows that Ln3GaO6 has a non-centro symmetric orthorhombic structure (space group Cmc2(1)). Lattice parameters a, b, c and cell volume and the average distances between Ln(l)-O, Ln(2)-O of these compounds decrease with the decreasing of the radii of trivalent Ln ions, which accord with the expected lanthanide contraction behavior. There are two sites of seven-fold coordination for Ln atoms with oxygens, and Ga atoms are in oxygen tetrahedra which are distorted and elongated along the a-axis. Magnetization measurements indicate that the susceptibility X changes with temperature in Curie-type manner. (C) 2004 Elsevier Inc. All rights reserved.

We have investigated the structure and magnetic properties of Pr 1− δ (Co,Cu) 5+2 δ (0 δ 7 -type structure, using X-ray powder diffraction and magnetic measurements. The lattice parameters ( a and c ) of Pr 1− δ (Co,Cu) 5+2 δ compounds increase with increasing Cu content since the radius of Cu is a little larger than that of Co. Our experimental results indicate that Cu may stabilize Pr 1− δ (Co,Cu) 5+2 δ compounds with the TbCu 7 -type structure, but δ is only determined by the temperature. The X-ray patterns of magnetically aligned samples show that the compounds with x =2.0 and 3.0 exhibit easy-plane magnetocrystalline anisotropy. The saturation magnetization and Curie temperature decrease with increasing Cu content.

The PrBa(2-x)Sr(x)Cu(3)O(7+/-delta) solid solution was investigated by means of X-ray powder diffraction in combination with Rietveld analysis. The Sr-doped Pr123 single phase could be synthesized at 950degreesC in air. The solubility of PrBa(2-x)Sr(x)Cu(3)O(7+/-delta) solid solution is 0.2 less than or equal to x less than or equal to 0.6. The structure of PrBa(2-x)Sr(x)Cu(3)O(7+/-delta) is orthorhombic for x = 0.2. The structure transforms into tetragonal for 0.3 less than or equal to x less than or equal to 0.6. In the PrBa(2-x)Sr(x)Cu(3)O(7+/-delta) structure, Sr ions can replace Ba ions, the highest value is x = 0.6 under our experimental condition. But Sr ions could not replace Pr ions. Furthermore Pr ions could not occupy the sites of Ba ions in the PrBa(2-x)Sr(x)Cu(3)O(7+/-delta) system. Both ionic radii and chemical properties play an important role in the mutual substitution of Pr, Ba and Sr ions in the Pr123 structure of the PrBa(2-x)Sr(x)Cu(3)O(7+/-delta) system. (C) 2003 Elsevier B.V. All rights reserved.

The coexistence of superconductivity and magnetic order seems to take place in the so-called ruthenate-cuprates (Ru-1212). A systematic study is carried out on crystal structure of the RuSr 2 R Cu 2 O 8− δ phases ( R =Gd, Tb, Dy, Y, Ho, Er) synthesized under high pressure by X-ray powder diffraction. RuSr 2 R Cu 2 O 8− δ ( R =Gd, Tb, Dy, Y, Ho, Er) has the Ru-1212-type structure of a tetragonal symmetry and the RuO 6 octahedra rotate around the c -axis with an additional small rotation around an axis perpendicular to c . The DC-magnetization data establish that compounds with R =Gd, Y, Ho, Er exhibit ferromagnetic order below about 140 K, and the Meissner effect was observed at low temperature for R =Y compound.

We have investigated the structural stability and magnetic properties of SMCo7-xCu, compounds with the TbCu7-type structure using x-ray powder diffraction and magnetic measurement. A large solid solution with 0.8 less than or equal to x less than or equal to 4.0 in SMCo7-xCux compounds has been observed. Both the lattice parameters and unit cell volume increase with increasing Cu content. SMCo7-xCux compounds exhibit ferromagnetic order. A strong uniaxial magnetocrystalline anisotropy with an anisotropy field as high as 20 T is obtained with x = 0.8 at 5 K. However, the saturation magnetization and Curie temperature decrease with increasing Cu content.

This study was to test the operation performance of a multifunctional air source heat pump in heating, refrigeration and the water heating mode by building the experimental platform. The heating capacity, refrigerating capacity and COP value of the multifunctional air source heat pump under different operating modes were obtained by experimental method. The existence problems of the multifunctional air source heat pump in the actual operation were found and the improvement direction was put forward. The study results could provide actual reference for the design and application of the multifunctional air source heat pump units.

The crystal structure and magnetic properties of Gd-5(Si1-xGex)(4) compounds (0 less than or equal to x less than or equal to 1.0) are investigated by means of temperature dependent X-ray powder diffraction and magnetic measurements. A crystallographic and magnetic phase diagram of the pseudobinary system Gd5Si4-Gd5Ge4 is constructed. An intriguing observation is that Gd-5(Si1-xGex)(4) alloys form a completely miscible solid-solution at low temperature (< T-C), crystallizing in the Gd5Si4-type structure as indicated by the well-defined linear dependence of lattice parameters on germanium concentration x, and decomposing into three partially miscible solid-solutions above the Curie temperature, i.e. Gd5Si4 based (x < 0.5), Gd5Ge4 based (x greater than or equal to 0.8) and Gd5Si2Ge2 based (0.5 less than or equal to x < 0.8) solid-solutions, This unusual feature can be understood by taking into account competing effects of ferromagnetic exchange interaction and lattice strain in the solid-solution. (C) 2001 Elsevier Science B.V. All rights reserved.

The effect of substitution of Ni for Co in the borides Nd/sub 3/(Co/sub 13-x/Ni/sub x/)B/sub 2/ (x=0, 1, 2, 3, 4, 5) on the crystal structure and magnetic properties has been investigated. The lattice parameter a decreases while c increases with increasing x in the range 0/spl les/x/spl les/5. The Curie temperature and saturation magnetic moment per formula unit in Nd/sub 3/(Co/sub 13-x/Ni/sub x/)B/sub 2/ decrease monotonically as the Ni concentration increases. We have observed spin-reorientation transitions at temperatures that decrease monotonically with increasing Ni concentration. It is noteworthy that the substitution of Ni has a significant effect on the magnetocrystalline anisotropy of the Co sublattice, leading to the change of easy magnetization direction of Nd/sub 3/(Co/sub 13-x/Ni/sub x/)B/sub 2/ compounds from basal plane to the c axis at room temperature when x/spl ges/2. The magnetic phase diagram of the Nd/sub 3/(Co/sub 13-x/Ni/sub x/)B/sub 2/ borides is given, and the behavior of magnetocrystalline anisotropy is analyzed by the single ion model.

The effect of the substitution of Sm, Nd and Ce for Gd on the structure and magnetic properties of (Gd1-x Rx )3 Fe28 Nb (R = Sm, Nd and Ce) compounds have been studied. The single-phase regions for R = Sm, Nd and Ce correspond to the composition range of 0 x 0.2, 0 x 0.5 and 0 x 0.4, respectively. All of the compounds crystallize in the Nd3 Fe29-x Tix -type structure. The lattice parameters a , b , c and V increase with the increase of the Sm and Nd content, while decrease with an increase of the Ce content. Substitution of Sm, Nd and Ce for Gd leads to a decrease of Curie temperature (TC ) and an increase of the saturation magnetization (MS ). The compounds (Gd1-x Smx )3 Fe28 Nb and (Gd1-x Ndx )3 Fe28 Nb exhibit planar anisotropy perpendicular to the [102] direction, the anisotropy field HA increases with the substitution content, while in compounds (Gd1-x Cex )3 Fe28 Nb, the planar anisotropy field HA decreases with an increase of the Ce content. (Gd0.6 Ce0.4 )3 Fe28 Nb exhibits an intermediate easy axis behaviour.

A series of Gd-3(Fe1-x-yCoyTix)(29) (x = 0.011-0.034, y = 0-0.393) Samples have been prepared. Single-phase samples assigned as 3:29 compounds with the monoclinic lattice are obtained in the following composition regions: x; = 0.011, 0 less than or equal to y less than or equal to 0.307; x = 0.022, 0 less than or equal to y less than or equal to 0.313; and x = 0.034, 0 less than or equal to y less than or equal to 0.393. The solid-solution limit of cobalt in Gd-3(Fe1-x-yCOyTix)(29) increases with the Ti content. The cell parameters a, b and c show anisotropic decreases with the Co content, i.e. a and b decrease significantly and c decreases slightly in the composition range investigated. The Curie temperature is increased by the substitution of Co for Fe in Gd-3(Fe1-x-yCoyTx)(29). The saturation magnetization first increases and then decreases with the Co content. The dependence of the intrinsic magnetic properties of Gd-3(Fe1-x-yCoyTix)(29) on the Co and Ti contents is presented. The compounds exhibit an easy-magnetization direction on the a-b plane corresponding to the CaCu5-type structure at room temperature. The anisotropy field H-a of Gd-3(Fe1-x-yCoyTix)(29) is decreased and the magnetocrystalline anisotropy constant K-1 is increased by the substitution of Co for Fe. No spin reorientation is observed in the alternating-current susceptibility measurement between 77 K and the Curie temperature.

The influence of R substitution in (La1-xRx)(2)Co16Ti compounds (R=Sm, Nd; x=0.0-1.0) on structural and magnetic properties has been investigated. The lattice parameters of the (La1-xRx)(2)Co16Ti compounds decrease with increasing x in the range 0 less than or equal to x less than or equal to 1.0. With x increasing, the saturation magnetic moment increases for (La1-xNdx)(2)Co16Ti while remains unaffected for (La1-xSmx)(2)Co16Ti. The Curie temperature increases with increasing Sm or Nd substitution. The uniaxial magnetocrystalline anisotropy of (La1-xSmx)(2)Co16Ti becomes enhanced with increasing Sm substitution. The anisotropy of (La1-xNdx)(2)Co16Ti changes from easy-axis (x 0.4). (C) 2000 Elsevier Science S.A. All rights reserved.

The effect of the substitution of Ni for Fe on the magnetic and structural properties of Gd-3(Fe28-xNix)(Nb1-y,Mo-y) (x less than or equal to 4, y=0.3 and 0.7) compounds have been studied. All of the compounds crystallize in the Nd3Fe29-xTix-type structure and the lattice parameters a, b, c and the unit cell volume V decrease with increasing Ni content. Substitution of Ni for Fe leads to a clear increase of the Curie temperature (T-C) and to a small decrease of the saturation magnetization (M-S). The compounds exhibit planar anisotropy perpendicular to the [102] direction. The anisotropy field H-A decreases with increasing Ni content. The effect of Ni substitution on the Curie temperature and the saturation magnetization are discussed. (C) 1999 Elsevier Science S.A. All rights reserved.

Subsolidus phase relations in the Go-rich region of the La-Go-Ti system have been investigated by means of X-ray diffraction. The phase diagram can be divided into six three-phase and three two-phase regions. In the investigated composition region, a new ternary compound exists: La2Co17-xTix (x=0.8-1.2) (Th2Zn17-type structure) (C) 2000 Elsevier Science S.A. All rights reserved.