On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry

Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky Way.Photometric surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution spectroscopy.In this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model spectra.We find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the metallicity.According to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,respectively.The precision of the effective temperature estimated from broad-band colors are within 50 K.

Association between Serum Uric Acid and the Early Marker of Kidney Function Decline among Chinese Middle-Aged and Older Population:Evidence from the China Health and Retirement Longitudinal Study

Objective To evaluate the association between serum uric acid(SUA)and kidney function decline.Methods Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older population for analysis.The kidney function decline was defined as an annual estimated glomerular filtration rate(e GFR)decrease by>3 mL/min per 1.73 m^(2).Multivariable logistic regression was applied to determine the association between SUA and kidney function decline.The shape of the association was investigated by restricted cubic splines.Results A total of 7,346 participants were included,of which 1,004 individuals(13.67%)developed kidney function decline during the follow-up of 4 years.A significant dose-response relation was recorded between SUA and the kidney function decline(OR 1.14,95%CI 1.03-1.27),as the risk of kidney function decline increased by 14%per 1 mg/d L increase in SUA.In the subgroup analyses,such a relation was only recorded among women(OR 1.22,95%CI 1.03-1.45),those aged<60 years(OR 1.22,95%CI 1.05-1.42),and those without hypertension and without diabetes(OR 1.22,95%CI 1.06-1.41).Although the dose-response relation was not observed in men,the high level of SUA was related to kidney function decline(OR 1.83,95%CI 1.05-3.17).The restricted cubic spline analysis indicated that SUA>5 mg/dL was associated with a significantly higher risk of kidney function decline.Conclusion The SUA level was associated with kidney function decline.An elevation of SUA should therefore be addressed to prevent possible kidney impairment and dysfunction.

几种巧克力调温过程中的结晶特性研究

本文用X－衍射法(XRD)和差示扫描量热法(DSC)对香菇巧克力(LC)，茶叶巧克力(TC)和对照样巧克力(CC)在调温工艺过程中的结晶特性进行了研究。发现3种巧克力在调温过程中的结晶行为各有其特性，这些特性在X－衍射(XRD)谱图中和热差法(DSC)熔解曲线上得到明显反映。LC和CC有相似的变化趋势。3种巧克力在浇模时所形成的晶相之熔点各不相同。LC为29.62℃，TC为21.93℃。CC为26.05℃，促霜试验表明：香菇和茶叶均有较好的延霜效果，其中香菇效果优于茶叶。

榴辉岩中传统地质温压计新解:来自PT视剖面图的证据

石榴石-单斜辉石(GC)温度计和石榴石-单斜辉石-多硅白云母(GCP)压力计是确定榴辉岩形成温压条件的最常用方法,二者主要依据石榴石、绿辉石和多硅白云母中相组分之间的交换和转换变质反应。依据MORB成分计算的PT视剖面图表明,在不同榴辉岩矿物组合中,控制3个矿物相成分变化的相组分之间的变质反应不同。在低温含绿泥石、滑石和蓝闪石榴辉岩组合中,石榴石和绿辉石的镁含量主要受到含水矿物脱水反应的控制,并都随温度升高而升高,二者之间的铁镁交换反应并不起主要作用。因此,在自然界含有蓝闪石等含水矿物的低温榴辉岩中,由于绿辉石相对富镁而常常导致GC温度计结果偏低。在含有硬柱石的高压-超高压榴辉岩中,石榴石中的钙含量受到硬柱石的控制,随着压力升高或温度降低,硬柱石含量增加,使石榴石中钙降低,此时石榴石-绿辉石-多硅白云母之间的转换反应对石榴石成分的影响会很微弱,由于石榴石相对贫钙而导致GCP压力计结果偏低。在含有蓝晶石的中温高压-超高压榴辉岩中,矿物成分的变化受到石榴石-绿辉石之间的铁镁交换反应和石榴石-绿辉石-多硅白云母-蓝晶石-石英/柯石英之间的一系列转换反应控制,因此,GC和GCP温压计都能给出相对合理的结果。在低压普通角闪石榴辉岩中,石榴石和绿辉石中的镁含量主要反应压力变化,有时并不指示变质作用温度。在含有蓝闪石等含水矿物的低温榴辉岩中,Thermocalc程序中的平均温压(avPT)方法可以给出比较合适的温度,但压力结果与GCP压力计一样也会偏低一些。在蓝闪石和绿帘石等含水矿物消失后的中温蓝晶石榴辉岩中,avPT方法难以给出合理的PT信息。相对来说,视剖面图方法能够给出最多的PT信息,是目前确定变质岩PT条件的最好方法。

内蒙古阿鲁科尔沁旗敖仑花斑岩铜钼矿床成矿时代和流体包裹体研究

内蒙古阿鲁科尔沁旗敖仑花铜钼矿床位于华北克拉通北缘西拉沐伦钼矿带,是典型的斑岩型铜钼矿床。对6件辉钼矿样品进行了铼-锇同位素分析,获得的等时线年龄为129.4±3.4Ma,表明成矿作用发生在早白垩世。根据成矿中的流体过程可分为三个阶段:早阶段以发育石英-黄铁矿脉为标志,中阶段是主要的成矿阶段,以发育石英-多金属硫化物脉为标志。这两个阶段的流体包裹体均一温度分别集中在330～430℃和250～350℃,盐度分别为1.06～>58.41 wt%NaCl eqv和0.88wt%～48.21 wt%NaCl eqv,两个阶段均为多种类型包裹体密切共生,均一温度接近而盐度相差悬殊,且两个阶段的包裹体均一方式多样,这些特征指示了这两个阶段的流体皆发生过沸腾作用。晚阶段以发育石英-碳酸盐细脉为标志,只有少量黄铁矿沉淀,该阶段仅发育富液相包裹体,均一温度<270℃.盐度低,范围为0.71 wt%～8.41 wt%NaCl eqv。激光拉曼光谱分析表明,早、中阶段包裹体的气相成分为H_2O和CO_2,而晚阶段气相中只含H_2O。总体来看,初始流体可能直接来自岩浆房中岩浆流体的上涌,具有高温、高盐度、高氧逸度和富CO_2等特点,在430℃和350℃时流体发生了两次沸腾作用,致使成矿物质快速沉淀,流体氧逸度降低,CO_2逃逸,到了晚期,流体包裹体中基本不再含有子晶和CO_2。

新疆西南天山木扎尔特河一带低压泥质麻粒岩岩石学特征、独居石U-Th-Pb定年及其地质意义

古南天山洋闭合过程中,由于洋壳俯冲产生的岛弧岩浆作用加热大陆地壳,在新疆西南天山木扎尔特一带形成了一套低压高温泥质麻粒岩相变质岩石。本文用Theriak-Domino热力学软件对该套岩石中的堇青石榴夕线石黑云母片麻岩和含夕线石堇青石榴黑云母片麻岩进行了岩石学相平衡计算研究,得到它们峰期变质的温压条件分别是:T=630～674℃,P=5.2～5.5kbar和T=645～684℃,P=5.4～5.7kbar。并采用独居石Th-U-Pb电子探针定年方法,对样品WQ006中的3颗独居石进行了原位年龄测定(38个分析点),得到2组等时线年龄,分别是376±8Ma和280±8Ma(2σ)。结合独居石的岩相学特征,提出了新疆西南天山低压高温麻粒岩相峰期变质作用的时代为280±8Ma,而376±8Ma(2σ)可能为原沉积岩的原岩/成岩年龄。表明西南天山洋壳开始俯冲发生在晚古生代,进一步证明了西南天山造山带俯冲碰撞发生在晚二叠纪之后的观点。

柴北缘锡铁山一带榴辉岩的岩石学特征及其退变PT轨迹

柴北缘锡铁山地区榴辉岩以透镜体的形式存在于花岗质片麻岩和副变质片麻岩中。根据矿物组合的不同,可以分为多硅白云母榴辉岩和角闪石榴辉岩。在多硅白云母榴辉岩中首次发现了柯石英假象.利用榴辉岩中Grt-Cpx-Phn矿物温压计,结合绿辉石中存在柯石英假象包体的现象,得到锡铁山榴辉岩的峰期温压条件为751～791℃,2.71～3.17GPa,证明了锡铁山地区与柴北缘其他地块一样,也经历了超高压变质作用。通过PT视剖面图计算了榴辉岩退变的PT轨迹具有2个阶段演化特征:即先等温降压,然后再降温降压的PT轨迹。详细的岩石学研究探讨了榴辉岩在退变过程中,各矿物的成分和结构的改变过程。石榴石在等温降压过程中成分变化不大,而在角闪石出现后,其边部镁铝榴石含量明显降低,进而形成了韭闪石+斜长石的冠状体。绿辉石在水饱和状态下经过贫硬玉化改造,而后形成了Di+Ab+Amp的后生合晶。多硅白云母分解形成白云母+黑云母及少量石英及钾长石的组合。角闪石随着温压条件的降低由钠钙质闪石逐渐向钙质闪石转化。

冀东晚古生代东湾子岩体的岩石成因研究

冀东晚古生代东湾子岩体由角闪石岩、少量辉石岩和辉长岩组成。典型的堆晶结构、全岩和镁铁质矿物(透辉石、角闪石)的上凸型稀土分布模式、相容元素含量低且变化范围大(如:角闪石岩中V=296×10^(-6)～673×10^(-6))的特征表明了岩体的堆晶成因。计算得到的与辉石岩中的透辉石相平衡的熔体具有很高的稀土含量,轻重稀土分馏较为明显,富集大离子亲石元素(如:Sr,Ba,K),亏损高场强元素(如:Nb,Zr,Ti),具有典型的弧岩浆特征。透辉石和角闪石的矿物成分也具有弧岩浆的特征。高钙透辉石、大量的角闪石与黑云母的存在说明母岩浆富水。透辉石在高P_(H_2O)的状态下与熔体反应,生成角闪石的结构特征也证明了这一点。结合岩体的球化学特征,认为岩浆来源于富集的含有角闪石的尖晶石橄榄岩的部分熔融,母岩浆具有富水的特征(>3%)。考虑到岩体形成时代(～300Ma;Zhao et al.,2007)和地质背景,认为东湾子岩体与位于华北北缘的其它晚石炭-早二叠世的岩体形成于同一构造背景下,都是晚古生代时期古亚洲洋向华北板块之下俯冲的产物。

Distribution of gyrA mutations in fluoroquinolone-resistant Helicobacter pylori strains

AIM:To investigate the resistance of Helicobacter pylori(H.pylori) to ciprofloxacin(CIP),levofloxacin(LVX) and moxifloxacin(MOX) in the Beijing area and to elucidate the resistance mechanisms.METHODS:Seventy-nine H.pylori clinical strains,isolated from patients who had undergone upper gastrointestinal endoscopy in Peking University First Hospital from 2007 to 2009,were tested for their susceptibility to CIP,LVX and MOX using the E-test method.H.pylori strain 26695 was included in the susceptibility testing as a control strain.According to the minimal inhibitory concentration(MIC) values,a strain was classified as resistant to CIP,LVX or MOX when the MIC was > 1 μg/mL.We amplified by polymerase chain reaction(PCR) and sequenced the quinolone resistance-determining regions of the gyrA and gyrB genes from 29 quinolone-resistant and 16 quinolone-susceptible H.pylori strains selected at random.RESULTS:In this study,the resistance rates of H.pylori to CIP,LVX or MOX were 55.7%(44/79),and the primary resistance rates were 26.6%(21/79).Patients with secondary resistance had received LVX in previous eradication treatments,but not MOX or CIP.Forty-five strains,including 29 CIP,LVX or MOX-resistant strains(MIC:1.5-32 μg/mL) and 16 susceptible strains,were selected randomly from the 79 strains and used in PCR analysis.Among these 45 strains,27 resistant strains had mutations in the gyrA gene,including 11 strains with mutations corresponding to Asp-91(MIC:2-32 μg/mL),one of which also had a mutation corresponding to Val-150,and 16 strains had mutations at Asn-87(MIC:4-32 μg/mL),three of which also had mutations corresponding to Arg-140 or Val-150.In addition,Arg-140,Val-150 or Ala-97 mutations were separately detected in three susceptible strains.Analysis of the gyrB gene showed that one strain of low resistance had a mutation corresponding to Ser-457 that coexisted with an Asp-91 mutation.There was a significant difference in the occurrence of mutations in the gyrA gene between CIP,LVX and MOX-resistant and-susceptible strains(P < 0.05),but 2 resistant strains were found to possess no quinolone resistance-determining region mutations.CONCLUSION:Resistance is primarily mediated through point mutations in gyrA.Whether other mechanisms are responsible for resistance in strains without mutations in the QRDR should be detected.

Inflammatory cytokine gene polymorphisms increase the risk of atrophic gastritis and intestinal metaplasia

AIM: To investigate the effects of interleukin-8 (IL-8 ), macrophage migration inhibitory factor (MIF ) gene polymorphisms, Helicobacter pylori (H. pylori ) infection, on the risk of developing severe chronic atrophic gastritis (SCAG) and intestinal metaplasia (IM). METHODS: A total of 372 cases were selected from a cohort study in Linqu County, a high risk area for gastric cancer (GC) in northern China. To obtain a sufficient group size, patients with normal or superficial gastritis were included. Based on an average follow-up period of 56 mo, the 372 cases were divided into no progres-sion group (no histological progression from normal or superficial gastritis, n = 137), group Ⅰ (progressed from normal or superficial gastritis to SCAG, n = 134) and group Ⅱ (progressed from normal or superficial gastritis to IM, n = 101). IL-8 , MIF gene polymorphisms were detected by polymerase chain reaction-based denaturing high-performance liquid chromatography analysis and DNA sequencing. RESULTS: An increased risk of SCAG was found in subjects with IL-8-251 AA genotype [odds ratio (OR) = 2.62, 95% CI: 1.23-5.72] or IL-8-251 A allele carriers (AA + AT) (OR = 1.81, 95% CI: 1.06-3.09). An elevated risk of IM was found in subjects with IL-8-251 AT genotype (OR = 2.27, 95% CI: 1.25-4.14) or IL-8-251 A allele carriers (OR = 2.07, 95% CI: 1.16-3.69). An increased risk of SCAG was found in subjects with MIF-173 GC genotype (OR = 2.36, 95% CI: 1.38-4.02) or MIF-173 C allele carriers (GC + CC) (OR = 2.07, 95% CI: 1.21-3.55). An elevated risk of IM was found in subjects with MIF-173 CC genotype (OR = 2.27, 95% CI: 1.16-4.46) or MIF-173 C allele carriers (OR = 3.84, 95% CI: 1.58-9.34). The risk of SCAG and IM was more evident in subjects carrying IL-8-251 A allele (OR = 6.70, 95% CI: 1.29-9.78) or MIF-173 C allele (OR = 6.54, 95% CI: 2.97-14.20) and positive for H. pylori infection. CONCLUSION: IL-8-251 and MIF-173 gene polymorphisms are significantly associated with the risk of SCAG and IM in a population with a high risk of GC in Linqu County, Shandong Province, China.

Profiling of microbial communities in a bioreactor for treating hydrocarbon-sulfide-containing wastewater

A technology of polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE)was used to profile the structure and dynamic changes of microbial communities in a bioreactor for treating hydrocarbon-sulfide-containing(HSC)wastewater.The results showed that the heterotrophic genus of Acinetobacter and the autotrophic genera of Thiobacillus and Thiomonas could survive well in all of three operating conditions.Some special genera were also observed with changes of micro-ecoenvironment in the reacto...

Level of circulating PD-L1 expression in patients with advanced gastric cancer and its clinical implications

Objective：The programmed cell death-1 receptor/programmed cell death-1 ligand （PD-1/PD-L1） pathway plays a crucial role in tumor evasion from host immunity.This study was designed to evaluate the association between circulating PD-L1 expression and prognosis in patients with advanced gastric cancer.Methods：Totally 80 advanced gastric cancer patients and 40 health controls from Beijing Cancer Hospital were enrolled in the present study.Circulating PD-L1 expression was tested by enzymelinked immunosorbent assay （ELISA）.The associations between the expression level of PD-L1 and clinicopathological features and prognosis were analyzed statistically.Results：Expression of PD-L1 in advanced gastric cancer patients was significandy up-regulated compared with health people （P=0.006）.The expression of PD-L1 was significantly correlated with differentiation and lymph node metastasis （P=0.026 and P=0.041,respectively）.Although we didn＇t find significant difference in all advanced gastric cancer patients with different PD-L1 expression,the adenocarcinoma patients with higher up-regulated PD-L1 expression had much better prognosis than low expression patients （65.6％ vs.44.7％,P=0.028）.Conclusions：PD-L1 was elevated in advance gastric cancer patients and may play an important role in tumor immune evasion and patients prognosis.

The MELD scoring system for predicting prognosis in patients with severe hepatitis after plasma exchange treatment

BACKGROUND: Hepatic failure caused by severe hepatitis is a clinical syndrome where the major liver functions, particularly detoxification, synthetic functions, and metabolic regulation are impaired to different degrees, and may result in major life-threatening complications such as hepatic encephalopathy, ascites, jaundice, cholestasis, bleeding and hepatorenal syndrome. Plasma exchange (PE) has been found useful in treating patients with fulminant hepatic failure by removing hepatic toxins and replacement of clotting factors, so PE treatment has temporary supportive effects on liver failure caused by severe viral hepatitis. in this study, our aim was to predict the prognosis of patients with severe hepatitis after PE treatment using the end-stage liver disease (MELD) scoring system. METHODS: Two hundred and twenty patients were randomly divided into PE and control groups, and the MELD score was calculated for each patient according to the original formula. The efficacy of PE was assessed by mortality or improvement in biochemical parameters and MELD score. RESULTS: The levels of total bilirubin and international normalised ratio (INR) in patients whose MELD scores were between 30 and 39 were lower than those before PE treatment, as those in patients whose MELD scores were 40 or higher. The mortality of patients in the PE group with MELD scores from 30 to 39 was 50.0%, while it was 83.3% in the control group (P<0.01). The mortality of patients with MELD scores higher than 40 was 90.0% in the PE group and 98.0% in the control group (P>0.05). CONCLUSIONS: PE treatment can decrease the serum total bilirubin level and INR and MELD score of patients with severe hepatitis and improve liver function. Compared with the control group, PE can significantly decrease the mortality of patients with MELD scores from 30 to 39, but has no effect in patients with MELD scores of 40 or higher.

Triptolide prolonged allogeneic islet graft survival in chemically induced and spontaneously diabetic mice without impairment of islet function

BACKGROUND: Triptolide (TPT) is a diterpenoid triepoxide extracted from the Chinese herb Tripterygium wilfordii Hook. F. It exhibits potent immunosuppressive and anti-inflammatory properties. This study was undertaken to investigate its effects on prolongation of islet allograft survival in rodents. Additionally, we investigated whether TPT would be toxic to islet function in vivo. METHODS: We transplanted BALB/c islets to either chemically induced diabetic C57BL/6 mice or spontaneously diabetic non-obese diabetic (NOD) mice. TPT was injected within 2 weeks or continuously, until rejection, in the two combinations. Then, we evaluated the toxicity of TPT on islet function by daily injection to naive BALB/c or diabetic BALB/c that was cured by syngeneic islet transplantation under the kidney capsule. Mice injected with cyclosporine A (CsA) or vehicle served as controls. Intraperitoneal glucose tolerance tests (IPGTTs) performed at 4 and 8 weeks in the naive BALB/c group, and at 2, 4, 6, and 8 weeks in the syngeneic transplanted group. RESULTS: The medium survival time of islets allograft from TPT treated C57BL/6 and NOD recipients were 28.5 days (range 24-30 days, n=10) and 33.0 days (range 15-47 days, n=6), respectively, and they were significantly different from those of the vehicle treated controls, which were 14.0 days (range 13-16 days, n=6) and 5.0 days (range 4-10 days, n=6), respectively (all P<0.0001). The IPGTT demonstrated that there was no difference between the TPT treated and vehicle treated groups, either in the normal or syngeneic transplanted islet BALB/c mice. However, CsA injection impaired islet function in both normal and syngeneic transplanted mice as early as 4 weeks. CONCLUSION: TPT prolonged islets allograft survival in a chemically induced diabetic or an autoimmune diabetic murine model without impairment of islet function. (Hepatobiliary Pancreat Dis Int 2010; 9: 312-318)

Diagnosis of bacterial hepatic abscess by CT

BACKGROUND: Bacterial hepatic abscess usually is acute and progressive, often resulting in sepsis, impairment of liver function and disseminated intravascular coagulation. The mortality rate was as high as 80% in the past. For the purpose of early diagnosis and differential diagnosis of this disease, we probed the imaging manifestations and their characteristics in bacterial hepatic abscesses by CT scan. METHODS: Twenty-four lesions from 21 patients with bacterial hepatic abscesses that were confirmed by clinical features, puncture and culture were reviewed for CT manifestations. Fourteen patients were male and 7 were female, with an average age of 56.2 years. All lesions underwent CT plain scan and three-phase enhanced scan and 15 patients underwent delayed-phase imaging. Three senior radiologists read the films in accordance with a standard. RESULTS: Among 24 lesions, 18 (75%) were situated in the right liver with diameters of 1.4-9.3 cm (average 4.5 cm). Nineteen (79.2%) lesions were round or sub-round in shape, and 22 (91.7%) had smooth, uninterrupted and sharp edges. All lesions showed low attenuation of less than 20 Hu. Twenty-two enhanced lesions (91.7%) had rim-shaped enhancement in the abscess wall, and 13 (54.2%) showed single or double-ring signs. Eighteen (75%) displayed honeycomb-like, grid-like or strip-like enhancement. Eighteen (75%) were regionally enhanced in the surroundings or upper or lower layers. Only 2 (8.3%) displayed a gas-liquid surface sign. CONCLUSIONS: The CT findings of bacterial hepatic abscess are usually typical, and the diagnosis of the abscess is not difficult. To precisely diagnose atypical cases, it is necessary to combine CT with clinical observations and follow-up.

Interaction of Nicotine and Bovine Serum Albumin

The binding of nicotine to bovine serum albumin (BSA) was studied by UV absorption. fluorescence, and H-1 NMR methods. With the addition of nicotine, the absorption band of BSA at about 210 nm decreased gradually, moved to longer wavelengths, and narrowed. BSA fluorescence of tryptophan residue was quenched by nicotine. The H-1 NMR peaks of nicotine moved to downfield by the addition of BSA. The experimental results showed that nicotine was capable of binding with BSA to form a 1:1 complex. BSA's high selectivity for nicotine binding suggests a unique role for this protein in the detoxification and/or transport of nicotine.

International Workshop on ＂Central Asian Orogenesis and Metallogeny＂

An ＂International Workshop on Central Asian Orogenesis and Metallogeny＂, sup- ported by Department of Science and Tech- nology of Xinjiang Uygur Autonomous Region, the Geosciences Department of the Natural Science Foundation of China, the Bureau of Science and Technology for Resources and Environment, the Chinese Academy of Science, Xinjiang Petroleum Company, and China National Petroleum Corporation, was held in Urumqi, Xinjiang, from 18-24 September, 2007 （hosted by the National 305 Project Office）.

北祁连山高压变质带的变形和变质特征及其对俯冲带折返的意义

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+Rut±Lws,硬柱石呈包裹体和假象分布于石榴石内,变质温压条件T=465～508℃,p=2.30～2.60GPa。(2)片状榴辉岩,岩石具片状构造,其共生矿物组合Omp+Czo/Ep+Phn+Gln构成透入性面理S_1和线理L_1,以及宏观和显微同斜褶皱F_1。其峰期变质温压条件为T=466～510℃,P=1.9～2.2GPa。(3)蓝片岩相退化变质榴辉岩,蓝片岩相变质矿物Gln+Ep+Phn±Ab强烈交代榴辉岩相矿物,并发生强烈D_2期变形作用,岩石形成明显的透入性面理S_2和线理L_2,以及同斜剪切褶皱F_2。蓝闪石和多硅白云母线理的统计揭示D_2期变形以斜向走滑剪切为主,与D_1期变形的榴辉岩的运动学特征大体相似。D_2同变质的温压条件为T=422～487℃,P=1.15～1.37GPa。高压变质带晚期的绿片岩相叠加和D_3期变形,形成透入性面理S_3和线理L_3,其运动特征为近于垂直构造线的逆冲剪切。结合榴辉岩变形特征,变质温压条件和同位素年代学资料,我们认为退变质的强弱与变形程度有密切关系。峰期变质后的榴辉岩经过早期绿帘石榴辉岩相到蓝片岩相斜向走滑剪切,和晚期绿片岩相逆冲,在泥盆纪早期快速折返的出露地表。

Near-optimal cumulative longitude low-thrust orbit transfer

The indirect method for the continuous low-thrust near minimum cumulative longitude orbit transfer problem is addressed.The movement of the satellite is described by the Gauss equation using the modified equinoctial elements and replacing time as the system independent variable by the cumulative longitude.The maximum principle is adapted to design the optimal control in order to minimize the final cumulative longitude, and the twopoint-boundary-value problem is derived from the orbit transfer problem.The single shooting method is applied in a numerical experiment, and the simulations demonstrate that the orbit transfer mission is fulfilled and the product of the maximal thrust and the minimum cumulative longitude is near constant.

Relationship of Purity Gradient and Accumulation with Feed Composition in Two-Component Countercurrent Extraction System

The formulations of the purity gradient and accumulation were proposed, and their relationships with purity distribution were studied in twocomponent countercurrent extraction system. By the static and dynamic simulation, the purity distribution curves with various feed composition and separation factor were interrelated, and the related purity gradient and accumulation were calculated. The results show that there are purity gradient maxima in extraction and scrubbing sections for each component in both aqueous and organic phases. The accumulation of each component in both phases increases with its content in the feed. Meanwhile, its absolute value of purity gradient decreases in extraction section and increases in scrubbing section. Furthermore, the purity gradient and accumulation as the monitoring parameters for automation were evaluated. The precision of the online analysis in the sensitive point and the range of accumulation were also estimated.