铌钛处理对汽车外板用烘烤硬化钢磷化特性的影响

在实验室模拟对比了经不同冶金工艺(加Nb及加Nb+Ti)处理的两种BH钢的磷化效果。利用扫描电镜SEM及电子探针EPMA分析发现,加Nb+Ti处理的BH钢磷化膜相对均匀稳定。结合GDS表面元素分析结果认为,相对低Mn成分及低温退火处理是获得高品质磷化膜的关键冶金影响因素。

Electrical Transport Properties of Annealed Undoped InP

The electrical properties of annealed undoped n type InP are studied by temperature dependent Hall effect (TDH) and current voltage ( I V ) measurements for semiconducting and semi insulating samples,respectively.Defect band conduction in annealed semiconducting InP can be observed from TDH measurement,which is similar to those of as grown unintentionally doped InP with low carrier concentration and moderate compensation.The I V curves of annealed undoped SI InP exhibit ohmic property in the applied field region up to the onset of breakdown.Such a result is different from that of as grown Fe doped SI InP which has a nonlinear region in I V curve explained by the theory of space charge limited current.

Biogeochemical characteristics of nitrogen and phosphorus in Jiaozhou Bay sediments

Sediment samples were cored from 3 locations representing the inner bay, the outer bay and the bay mouth of Jiaozhou Bay in September 2003 to study the source and biogeochemical characteristics of nitrogen and phosphorus in the bay. The content and vertical distributions of total nitrogen (TN), total phosphorus (TP), organic nitrogen (ON), organic phosphorus (OP), inorganic nitrogen (IN), inorganic phosphorus (IP), the ratio of organic carbon and total nitrogen (OC/TN), and the ratio of total nitrogen and total phosphorus (TN/TP) in the sediments were analyzed. The results show that both TN and TP in surface sediments decrease from the inner bay to the outer bay. In general, ON occupies 50%?70% of TN and IP accounts for more than 60% of TP. In ratio of OC:TN, the nitrogen accumulated in the sediments from the inner bay and the bay mouth came mainly from terrestrial sources, and the portion of autogenetic nitrogen was 28.9% and 13.1%, respectively. However, in the outer bay, nitrogen was mainly autogenetic, accounting for 62.1% of TN, whereas phosphorus was mainly land-derived. The sedimentation fluxes of nitrogen and phosphorus varied spatially. The overall diagenesis rate of nitrogen was higher than that of phosphorus. Specifically, the diagenesis rate of OP was higher than that of IP. However, the diagenesis rate of ON was not always higher than that of IN. In species, the diagenesis rate of IN is sometimes much higher than that of the OC. In various environments, the diagenesis rate is, to some degree, affected by OC, pH, Eh, and Es.

Effects of Phosphine on Germination and Physiological Characteristics of Rice Seeds

[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase （CAT） and peroxidase （POD） were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde （MDA） was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.

Identification and Metabolic Mechanism of Non-fermentative Short-cut Denitrifying Phosphorus-removing Bacteria

To investigate the characteristics and metabolic mechanism of short-cut denitrifying phospho- rus-removing bacteria （SDPB） that are capable of enhanced biological phosphorus removal （EBPR） using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand （COD）, phosphate, nitrite, poly-fl-hydroxybutyrate （PHB）, and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release （96.2%） under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation （91.3%） and a little for glycogen synthesis （8.7%）. This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms （PAOs）. It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring AP/APHB and ANO2 -N/APHB is more necessary than monitoring AP/ACOD, ANO2 -N/ACOD, or AP / ANO2 -N.

Characteristics of deslanoside-induced modulation on jejunal contractility

AIM:To characterize the dual effects of deslanoside on the contractility of jejunal smooth muscle.METHODS:Eight pairs of different low and high contractile states of isolated jejunal smooth muscle fragment(JSMF) were established.Contractile amplitude of JSMF in different low and high contractile states was selected to determine the effects of deslanoside,and Western blotting analysis was performed to measure the effects of deslanoside on myosin phosphorylation of jejunal smooth muscle.RESULTS:Stimulatory effects on the contractility of JSMF were induced(45.3% ± 4.0% vs 87.0% ± 7.8%,P < 0.01) by deslanoside in 8 low contractile states,and inhibitory effects were induced(180.6% ± 17.8% vs 109.9% ± 10.8%,P < 0.01) on the contractility of JSMF in 8 high contractile states.The effect of deslanoside on the phosphorylation of myosin light chain of JSMF in low(78.1% ± 4.1% vs 96.0% ± 8.1%,P < 0.01) and high contractile state(139.2% ± 8.5% vs 105.5 ± 7.34,P < 0.01) was also bidirectional.Bidirec-tional regulation(BR) was abolished in the presence of tetrodotoxin.Deslanoside did not affect jejunal contractility pretreated with the Ca 2+ channel blocker verapamil or in a Ca 2+-free assay condition.The stimulatory effect of deslanoside on JSMF in a low contractile state(low Ca 2+ induced) was abolished by atropine.The inhibitory effect of deslanoside on jejunal contractility in a high contractile state(high Ca 2+ induced) was blocked by phentolamine,propranolol and L-NG-nitroarginine,respectively.CONCLUSION:Deslanoside-induced BR is Ca 2+ dependent and is related to cholinergic and adrenergic systems when JSMF is in low or high contractile states.

Magnetic Properties of the Phosphorous and Carbon with a Four and Five Bonds

The authors discovered a new magnetic properties of the phosphorous and carbon with a four and five bond, and stibine, bismuthine in organometallic chemistry. This allows to modify many of classical reactions by replacing with the nitrogen atoms to atoms of phosphorus, arsenic, antimony and bismuth. The authors have proposed a new mechanism for the possible reactions.

Phosphorus Use Efficiency of Bio-Based Fertilizers:Bioavailability and Fractionation

Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and CaCl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. Moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.

Zic1 negatively regulates brown adipogenesis in C_3H_(10)T_(1/2) cells

Zinc finger in the cerebellum 1 （Zicl） is known to regulate neurogenesis and myogenesis in the develop- mental stage and widely used as one of the brown adipocyte-specific markers. In this study, we examined the effect of Zicl on brown adipogenesis. Overexpression of Zicl attenuated the lipid accumulation and the expressions of PPAR72 and C/EBPα in C3H10T1/2 mesenchymal stem cells. The mRNA levels of BAT-specific thermogenic genes （PRDM16, PGC-1α and UCP1） and fatty acid oxidation regulatory genes （PPARα, CPT1α, CPT1β and COX7α1） were suppressed in Zicl-overexpressed cells. Moreover, overexpression of Zicl reduced the mitochondrial oxidative phosphorylation （OXPHOS） regulatory proteins including ATP5α, UQCRC2, SDHB and NDUFB5. These results indicate a potential role of Zicl in the regulation of brown adipogenesis via inhibiting adipogenesis, fatty acid oxidation and mitochondrial OXPHOS.

Remarkable anisotropic phonon response in uniaxially strained few-layer black phosphorus

Black phosphorus （BP） is a good candidate for studying strain effects on two- dimensional （2D） materials beyond graphene and transition-metal dichalcogenides. This is because of its particular ability to sustain high strain and remarkably anisotropic mechanical properties resulting from its unique puckered structure. We here investigate the dependence of lattice vibrational frequencies on cry- stallographic orientations in uniaxially strained few-layer BP by in-situ strained Raman spectroscopy. The out-of-plane A1 mode is sensitive to uniaxial strain along the near-armchair direction whereas the in-plane B2g and A2 modes are sensitive to strain in the near-zigzag direction. For uniaxial strains applied away from these directions, all three phonon modes are linearly redshifted. Our experimental observation is explained by the anisotropic influence of uniaxial tensile strain on structural properties of BP using density functional theory. This study demonstrates the possibility of selective tuning of in-plane and out-of-plane phonon modes in BP by uniaxial strain and makes strain engineering a promising avenue for extensively modulating the optical and mechanical properties of 2D materials.

Effect of total phosphorous pollution on cavitation pressure characteristics of working water used in turbines

Many experiments have proven that with increasing silt and gas(out-of-phase media)content in water,the cavitation characteristics change and the cavitation pressure increases.Currently,many large reservoirs in China are polluted by total phosphorus(TP)and other chemical contaminants because of the use of phosphate fertilizer runoff from agriculture.However,research regarding how chemical pollutants(in the form of out-of-phase media)affect the cavitation pressure characteristics of water is sparse.In this paper,the Goupitan Hydropower Station,the largest hydropower reservoir on the Wujiang River,which is heavily polluted by TP,is taken as an example to evaluate the effects of chemical pollution on water cavitation pressure characteristics.In this study,the cavitation pressure characteristics of polluted and clean water are compared.The results show that the cavitation pressure of water polluted by chemicals is larger than that of clean water.In a hydraulic power generation system,cavitation and cavitation erosion are likely to occur earlier in runners when the fluid is polluted.These results are of great importance to further studies of cavitation theory and can directly influence the arrangement of turbines in practical engineering.