磷石膏综合利用现状及“十四五”发展趋势

我国磷石膏综合利用已位居世界领先水平,综合利用途径多样化,但也存在对磷石膏认识不清,创新动力不足,上下游产业协同不足等问题亟待解决。“双碳”战略的实施,对磷石膏资源综合利用既是机遇又是挑战。基于此,介绍国内外磷石膏资源综合利用现状,重点阐述中国磷石膏产生利用情况。随着中国磷肥生产工艺、技术及管理水平的提升,磷石膏品质逐步提高,磷肥副产的磷石膏量逐渐减少,磷石膏资源综合利用量和利用水平将不断提升。     

Is “Delayed Onset Muscle Soreness” a False Friend? The Potential Implication of the Fascial Connective Tissue in Post-Exercise Discomfort

Strenuous and unaccustomed exercise frequently lead to what has been coined “delayed onset muscle soreness” (DOMS). As implied by this term, it has been proposed that the associated pain and stiffness stem from micro-lesions, inflammation, or metabolite accumulation within the skeletal muscle. However, recent research points towards a strong involvement of the connective tissue. First, according to anatomical studies, the deep fascia displays an intimate structural relationship with the underlying skeletal muscle and may therefore be damaged during excessive loading. Second, histological and experimental studies suggest a rich supply of algogenic nociceptors whose stimulation evokes stronger pain responses than muscle irritation. Taken together, the findings support the hypothesis that DOMS originates in the muscle-associated connective tissue rather than in the muscle itself. Sports and fitness professionals designing exercise programs should hence consider fascia-oriented methods and techniques (e.g., foam rolling, collagen supplementation) when aiming to treat or prevent DOMS.     

泸天化大甲醇J0301/JT0301、J0201/JT0201压缩机吊装综述

利用150t履带吊车的理想站位,采用三钢扁担联合吊装法成功地将进口压缩机吊装到位。     

国外(摘0201—0220)

<正> 摘0201 TQ054.2 散粒物料加工炉——等;苏联发明证书№715;911,公布日期1980,2,15,申请日期1973,3,22。本发明是用来分解碳酸氢钠制取纯碱。目的是强化液体和加热物料之间的传热。为了达到此目的,在转鼓外面给炉子补充安装一台泵,泵用管子与内外蛇管连通,并和转鼓一起转动。文中有炉子纵断面示意图。 [1980,18 33]     

“Antiplasticization” in starch-glycerol films?

Calorimetric, mechanical, and thermomechanical properties have been measured on starch films with various glycerol/water contents. For calorimetric measurements, a continuous decrease in T_g was observed as glycerol increases from 0 to 25%. Mechanical properties exhibit a minimum of elongation at break for glycerol content ∼ 12%. In slightly hydrated starch films not containing another plasticizer, a β relaxation is detected by DMTA around −68°C. This relaxation is modified by the presence of glycerol, the α relaxation of which appears in the same temperature range. Results are discussed comparing with the well-known antiplasticization effect in synthetic polymers such as PVC and PC. The combination of the plasticizer α mode and the polymer β mode is considered. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1047–1053, 1997     

Possible proton conduction in Ce<Subscript>0.9</Subscript>Gd<Subscript>0.1</Subscript>O<Subscript>2−δ</Subscript> nanoceramics

Dense samples of Ce_0.9Gd_0.1O_2−δ with grain sizes in the range 91–252 nm were prepared and their electrical properties studied by impedance spectroscopy. It was found that the bulk conductivity is not affected by grain size or atmosphere and that small grain sizes lead to a larger total resistance of the material. The most striking result corresponds to a sample sintered in wet air that exhibited electrical characteristics that hint clearly at the presence of proton conduction at temperatures below 200 °C.     

Synthesis of SiO<Subscript>2</Subscript>–SnO<Subscript>2</Subscript> gels in water free conditions

A series of SiO₂–SnO₂ samples with various Sn/Si molar ratios (0.05–1.0) have been synthesized by the sol–gel technique from (Tetraethylorthosilicate) TEOS and Sn(CH₃COO)₄ precursors in water free conditions. The synthesis applied allowed obtaining the final product in monolithic (nonfractured upon drying) form with no use of drying control chemical additives. All samples are characterized by thermal analysis, XRD, and FTIR. The low temperature nitrogen adsorption measurements indicate the presence of both micro and mesopores. The samples containing less than 20 wt% of SnO₂ show much higher surface area than SiO₂ gel. The appearance of new bands at 1,048 and 882 cm⁻¹ in the FTIR spectra could be related to stretching vibrations of the three dimensional Si–O–Sn network, which suggests that tin component has replaced silicon atoms in Si–O–Si structure.     

Electrochemical promotion in O<Superscript>2−</Superscript> cells during propane oxidation

The catalytic oxidation of propane was studied in an oxygen ion conducting solid electrolyte cell at 623–773 K and atmospheric total pressure. Three catalyst-electrodes were tested, Pt, Pd and Ag. Under open circuit, the technique of Solid Electrolyte Potentiometry (SEP) was used to monitor the thermodynamic activity of oxygen adsorbed on the catalyst surface during reaction. Under closed circuit, the effect of electrochemical promotion was investigated. On Pt and Pd, the promoting effect was of the “inverted volcano” type. On Pt, the reaction exhibited a strong NEMCA effect; the closed circuit rate exceeded the open circuit rate by more than three orders of magnitude. On Pd, on the other hand, the effect was hardly Faradaic. On Ag, a moderate NEMCA behavior was observed and the promoting effect was purely electrophobic. Both open and closed circuit results obtained with these three catalyst-electrodes, are evaluated and compared to each other.     

Phase relationships in the Na<Subscript>2</Subscript>ZnP<Subscript>2</Subscript>O<Subscript>7</Subscript>–LiKZnP<Subscript>2</Subscript>O<Subscript>7</Subscript> system

The phase relationships in the Na₂ZnP₂O₇–LiKZnP₂O₇ system are studied. They are represented by a mixture of the starting components in the subsolidus region. The eutectic was found at a temperature of 640°C and composition of 0.5LiKZnP₂O₇. The phase formation of this system is compared with the previously studied NaKZnP₂O₇–LiKZnP₂O₇ system. It is shown that a structural factor affects the geometry of the state diagrams.     

Differences in Δ<Superscript>9</Superscript> desaturase activity between jersey-and limousin-sired cattle

An experiment examined Δ⁹ desaturase activity and FA composition in subcutaneous adipose tissue in two differing breeds of cattle. Jersey-sired cattle had significantly higher rates of desaturase activity than Limousin-sired cattle (1.55 vs. 0.75 nmol/mg protein/min). This difference was also demonstrated by a lower concentration of individual (e.g. 18∶0) and total saturated FA (38.3 vs. 45.1 wt%), and a higher concentration of individual (e.g., 16∶1) and total monounsaturated FA (58.2 vs. 52.7 wt%) in the Jersey animals. Other indices of desaturation calculated from the FA composition showed this same difference. The slip point of adipose tissue of Jersey cattle (36.8°C) was significantly lower than that of Limousin cattle (39.2°C), but Jersey adipose tissue had a greater content of β-carotene. The positive relationship between adipose tissue β-carotene and desaturation opposes the negative relationship between dietary β-carotene and desaturation determined elsewhere. These results, however, lead to the hypothesis that some cattle have a reduced capacity to metabolize β-carotene to various forms of vitamin A, a compound that can reduce Δ⁹ desaturase enzyme activity. In addition, the higher level of intramuscular fat in Jersey cattle (6.97 vs. 3.82%) is possibly related to a lack of inhibition of the adipocyte differentiation genes by vitamin A.     

Electrochromism in composite WO<Subscript>3</Subscript>–Nb<Subscript>2</Subscript>O<Subscript>5</Subscript> thin films synthesized by spray pyrolysis technique

Composite WO₃–Nb₂O₅ thin films were deposited on the glass and fluorine-doped tin oxide (FTO)-coated glass substrates using simple and inexpensive spray pyrolysis technique. The process parameters, like nozzle-to-substrate distance, spray rate, concentration of sprayed solution, etc., were optimized to good quality films. The films were characterized for the structural, morphological, optical, and electrochromic properties. Structural and morphological characterizations of the films were carried out using scanning electron microscopy and X-ray diffraction techniques. Electrochemical properties of the Composite WO₃–Nb2O₅ thin films were further studied using cyclic-voltammetry, chronoamperometry, chronocoulometry, and electrochemical Impedance spectroscopy.     

Role of CeO<Subscript>2</Subscript> in Rh/α-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> Catalysts for CO<Subscript>2</Subscript> Reforming of Methane

Abstract  

The Rh/α-Al₂O₃ catalyst was modified by CeO₂ in order to improve the thermal stability and the carbon deposition resistance during the CO₂ reforming of methane The carbon formation was determined by TPO, TEM and Raman spectroscopy. Characterization results showed that the incorporation of Ce in the support inhibits the carbon deposition, increasing the useful life and the stability of the Rh base catalysts.     

Formation of the bubble structure in the 26Li<Subscript>2</Subscript>O · 74SiO<Subscript>2</Subscript> glass

The formation of a bubble structure in the glass of composition 26Li₂O · 74SiO₂ is investigated. The stable reproducible characteristics of the bubble structure are obtained, namely, dependences of the number of bubbles on the conditions of glass synthesis, i.e., the synthesis temperature, the synthesis time, and the type of initial reagents. It is shown that the number of bubbles decreases with an increase in the height of the sample (glass melt in the crucible), as well as with an increase in the synthesis temperature at a fixed synthesis time or with an increase in the synthesis time for each specific temperature. The bubble size distribution curves are obtained for all synthesis conditions. The reproducible bubble structure is determined for each layer of the glass sample, which is subsequently used in studying the kinetics of heterogeneous nucleation.     

In‐situ‐EPR‐Spektroskopie in der heterogenen Katalyse: Stiefkind oder Lichtblick?

This review evaluates the potential of electron paramagnetic resonance (EPR, also known as electron spin resonance, ESR) as an in situ technique for analyzing structure‐reactivity relationships in heterogeneous catalysis under reaction condition. It starts with a general overview on the state of the art, followed by a short introduction of its theory. In due course the use of the method is illustrated by three selected application examples. At the end a critical evaluation of opportunities and limitations of in situ EPR in heterogeneous catalysis is given.     

Mating Disruption of <Emphasis Type="Italic">Paralobesia viteana</Emphasis> in Vineyards Using Pheromone Deployed in SPLAT-GBM™ Wax Droplets

A paraffin wax formulation releasing pheromone for mating disruption of insects was tested during 2005 and 2006 in Vitis labrusca vineyards infested by grape berry moth, Paralobesia viteana (Lepidoptera: Tortricidae). In early May of each year, 1-ml droplets of SPLAT-GBM wax containing 3% sex pheromone of P. viteana were applied to every wooden post at a rate of 400/ha in replicated 1.3-ha plots. Moth captures in sex pheromone baited traps placed at the vineyard borders and interiors revealed significant disruption of male moth captures in treated plots, with activity of one application lasting over 10 weeks during both years. Treatment with SPLAT-GBM did not affect the proportion of clusters infested until the end of the second growing season, when infestation was 27% lower in the treated plots than in the control plots. Comparisons of moth captures in traps placed inside 15.2 x 16.5 m vine plots that were untreated or received varying densities of 0.2-ml wax drops or Isomate-GBM hand-tied dispensers at the recommended rate of 450/ha indicated that orientational disruption increased with droplet density. Similar numbers of moths were captured in plots that received 10 or 30 drops per vine as were trapped in plots with twist ties spaced at 0.4 per vine. Moth captures in monitoring traps baited with increasing sizes of wax droplets (0.2, 0.5, or 1-ml drops) or red septa containing P. viteana sex pheromone suggest decreasing ability of male moths to reach traps with increasing pheromone loading. This study indicates that wax-deployed pheromone can reduce crop infestation by P. viteana after 2 years of deployment, and that the increasing of pheromone release by using application of greater droplet densities or by using larger droplets will improve the level of disruption achieved.     

Effect of phenol on Β-carotene content in total carotenoids production in cultivation of<Emphasis Type="Italic">Rhodotorula glutinis</Emphasis>

The composition of carotenoids produced byR. glutinis was observed to be dependent upon the addition of phenol into medium. A stimulatory effect of phenol on Β-carotene ofRhodotorula glutins K-501 grown on glucose was investigated. Carotenoids produced byRhodotorula glutinis K-501 were identified to torularhodin, torulene and Β-carotene, whose composition was 79.5%, 6.4% and 14.1%, respectively. The Β-carotene content increased up to 35% when phenol was added to culture media at 500 ppm. The ratio of torularhodin decreased with increasing phenol concentration, while torulene content was almost constant.     

Synthesis and Physicochemical Properties of Nanopowders and Ceramics in a CeO<Subscript>2</Subscript>–Gd<Subscript>2</Subscript>O<Subscript>3</Subscript> System

Nanopowders with a composition of (СeO₂)_1–x(Gd₂O₃)_x (x = 0.03, 0.05, 0.07, and 0.10) are synthesized by the coprecipitation method using cryotechnologies. The coherent scattering region (CSR) of the powders is 10–14 nm and the specific surface area is 70–81 m²/g. Based on the powders, ceramic nanosized materials with CRS of 64–71 nm are obtained. The dependence of the phase composition, microstructure, and electrical transport properties of the obtained samples on the Gd₂O₃ content is established. In a CeO₂–Gd₂O₃ system, a solid solution with the composition of (CeO₂)_0.90(Gd₂O₃)_0.10 has the highest ionic conductivity with the transfer number of ions of t_i = 0.74 at a temperature of 700°C. It is shown that ceramics of this composition can be used as a solid electrolyte of intermediate-temperature fuel cells due to their physicochemical characteristics.