αDecay in extreme laser fields within a deformed Gamow-like model

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely canceled.The remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

碳纤维主梁风电叶片防雷系统的仿真和试验研究

随着风力机装机容量的增加,风力机叶片越来越长也越来越重,要同时满足强度与刚度的要求,最有效的办法是采用碳纤叶片。碳纤维材料自身具有导电性,非常容易引雷而导致叶片发生重大损伤,必须开发出一套专门应用于碳纤维叶片的防雷系统。以某型号风电叶片为研究对象,在理论计算的基础上,通过采用铜网+接闪器组合的方式来提升防雷效果。通过雷电数值仿真和直接雷击试验等方式对防雷设计进行验证。仿真和试验结果表明:该防雷设计可有效引接雷电并保护碳纤维主梁结构,具有良好的防雷效果。

Empirical research on construction of a measurement framework for tourism carbon emission in China

According to the logic process of carbon reduction in China which arises from the measurement to reduction,from reduction to offsetting,the measurement of carbon emission in the tourism industry was the first and key step.Based on the life cycle assessment theory and input-output analysis,this article used economic and environmental measurement technologies,The System of National Accounting(SNA),Tourism Satellite Account(TSA),System of Integrated Environment and Economic Accounting(SEEA),and so on,and built up a top-down carbon emission analysis framework for the tourism industry and estimated carbon emission of the tourism industry in China in 2007.The finding showed that the total carbon emission of the tourism industry in China in 2007 was 169.78 million tons,covering 2.71%of carbon emission of all industries in China in 2007,and 2.44%of the total carbon emission in China in 2007.The direct carbon emission of the tourism industry in China in 2007 was 73.56 million tons,including transportation(50.14 million tons),sightseeing(1.33 million tons),lodging(4.19 million tons),accommodation(4.73 million tons),shopping(8.14 million tons),entertainment(0.67 million tons),communication(0.45 million tons),and others(3.90 million tons).The indirect carbon emission of the tourism industry in China in 2007 was 96.23 million tons,mostly contributed by coking,gas,and petroleum processing industries,transportation and warehousing industry,machinery and equipment manufacturing industry,and food manufacturing and tobacco processing industry,which covered 57%.

Ecosystem-driven karst carbon cycle and carbon sink effects

It is recognized that karst processes are actively involved in the current global carbon cycle based on twenty years research,and the carbon sink occurred in karst processes is possibly an important part of“missing sink”in global carbon cycle.In this paper,an overview is given on karst carbon cycle research,and influence factors,formed carbon pools(background carbon sink)and sink increase potentials of current karst carbon cycle are analyzed.Carbonate weathering could contribute to the imbalance item(BIM)and land use change item(ELUC)in the global carbon cycle model,owing to its uptake of both atmospheric CO_(2)(carbon sink effect)and CO_(2) produced by soil respiration(carbon source reduction effect).Karst carbon sink includes inorganic carbon sink resulted from hydrogeochemical process and organic carbon sink generated by aquatic photosynthetic DIC conversion,forming relatively stable river(reservoir)water body or sediment carbon sink.The sizes of both sinks are controlled by terrestrial ecosystems and aquatic ecosystems,respectively.Desertification rehabilitation and carbon sequestration by aquatic plants are two effective ways to increase the carbon sink in karst area.It is estimated that the rate of carbon sink is at least 381000 t CO_(2)/a with vegetation restoration and afforestation in southwest China karst area,while the annual organic carbon sink generated by aquatic photosynthesis is about 84200 t C in the Pearl River Basin.The development of a soil CO_(2) based model for assessment of regional dissolution intensity will help to improve the estimation accuracy of carbon sink increase and potential,thus provide a more clear and efficient karst sink increase scheme and pathway to achieve the goals of“double carbon”.With the deep investigation on karst carbon cycle,mechanism and carbon sink effect,and the improvement of watershed carbon sink measurement methods and regional sink increase evaluation approaches.Karst carbon sink is expected to be included in the list of atmospheric CO_(2) sources/sinks of the global carbon budget in the near future.

Carbon emission reduction: Contribution of karst carbon sinks and practice in China

Carbonate rocks, as soluble rocks, will dissolve and experience karstification driven by flowing water. This process consumes CO_(2)from the air and converts atmospheric CO_(2) and CO_(3)^(2-)of rocks into HCO_(3)^(-), resulting in the transfer of carbon from the atmosphere to the hydrosphere. Part of those dissolved HCO3-in the groundwater and surface water will degrade as CO_(2) and return to the atmosphere.

A novel S1P1 modulator IMMH002 ameliorates psoriasis in multiple animal models

Psoriasis is characterized by abnormal proliferation of keratinocytes,as well as infiltration of immune cells into the dermis and epidermis,causing itchy,scaly and erythematous plaques of skin.The understanding of this chronic inflammatory skin disease remains unclear and all available treatments have their limitations currently.Here,we showed that IMMH002,a novel orally active S1 P1 modulator,desensitized peripheral pathogenic lymphocytes to egress signal from secondary lymphoid organs and thymus.Using different psoriasis animal models,we demonstrated that IMMH002 could significantly relieve skin damage as revealed by PAS I score and pathological injure evaluation.Mechanistically,IMMH002 regulated CD3+T lymphocytes re-distribution by inducing lymphocytes’homing,thus decreased T lymphocytes allocation in the peripheral blood and skin but increased in the thymus.Our results suggest that the novel SIP1 agonist,IMMH002,exert extraordinary capacity to rapidly modulate T lymphocytes distribution,representing a promising drug candidate for psoriasis treatment.

Pharmacokinetics of H002, a novel S1PR_1 modulator, and its metabolites in rat blood using liquid chromatography–tandem mass spectrometry

A rapid and sensitive liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed and validated for the simultaneous determination of H002 and its phosphorylated metabolite, H002-P and hydroxylated metabolite H002-M, in rat blood. H001, an analogue of H002, was used as the internal standard.Blood samples were prepared by simple protein precipitation. The analytes and internal standard were separated on a Zorbax SB-C18 column with a gradient mobile phase consisting of methanol and water containing 0.1% formic acid at a flow rate of 0.2 mL /min with an operating temperature of 20 1C. The detection was performed on a triple quadrupole tandem mass spectrometer with positive electrospray ionization in multiple-reaction monitoring mode.Linear detection responses were obtained from 0.2–100 ng/mL for H002 and H002-M, while 0.5–100 ng/mL for H002-P. The intra- and inter-day precision(RSD%) was within 11.76%, with the accuracy(RE%) ranging from –9.84% to 9.12%. The analytes were shown to be stable during sample storage, preparation and analytic procedures.The method was applied to determine the pharmacokinetics of H002 in rats, and a preliminary study showed that the pharmacokinetics of H002 correlated with its biological effect on peripheral blood lymphocytes.

Synthesis of tetrahydroisoquinolines through TiCl4-mediated cyclization and Et3SiH reduction

A versatile and efficient telescoped reaction sequence for the synthesis of tetrahydroisoquinolines(THIQs)is reported that uses TiCl4 to promote cyclization of a benzylaminoacetal derivative and Et3SiH for reduction of the intermediate 4-hydroxy-THIQ.This method is complimentary to the classical Pomeranz-Fritsch and related reactions since it tolerates electron-withdrawing substituents and allows access to 8-substituted THIQs.

Design and synthesis of selective sphingosine-1-phosphate receptor 1 agonists with increased phosphorylation rates

FTY720 and IMMH002,prodrugs for sphingosine-1-phosphate receptor 1(S1P1)agonists,show inadequate and inconsistent levels of phosphorylation in humans compared to that in rats.In this study,FTY720 or IMMH002 analogues(21-24)were designed and synthesized with modified head pieces to improve the biotransformation of the prodrugs to the active phosphorylated forms.Target compounds were synthesized via a convergent route using the key and optically pure building block 9,which was first synthesized via asymmetrically catalyzed amination.The phosphorylation rates of these analogues in rat or human blood were compared.The new methyl-substituted analogue compound 21 showed higher phosphorylation rates in both rats and humans than the parent compound,whereas compound 23 showed improvements in rats,but not in humans.In pharmacokinetics studies of rats,compounds 21 and 23 both had higher levels of phosphorylation than FTY720 and IMMH002.Thus,our study not only yielded new compounds with therapeutic potential,but also showed species differences between rats and humans in response to the structural modifications,which might be useful for predicting the biotransformation behavior and efficacy of this class of prodrugs in the clinic.