Elemental Compositions of Clinopyroxenes from Southern Okinawa Trough Basalt:Implications for Magmatism and Structural Environment in an Initial Back-Arc Basin

The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initial back-arc basin at a continental margin.The clinopyroxenes in the basalt were augite with variable Mg^(#)contents(73.37-78.22).The regular variations in major oxide contents(i.e.,CaO,FeO,TiO_(2),and Cr)with decreasing Mg#implied that the clinopyroxenes evolved from being enriched in Mg,Ca,and Cr to being enriched in Fe and Ti.The clinopyroxenes had relatively low rare earth element concentrations(7.51×10^(-6) to 12.68×10^(-6))and negative Eu anomalies(δEu=0.67-0.95).The Kd_(cpx) values of clinopyroxenes(0.2-0.26),which were used to examine whether the clinopyroxene was equilibrated with its host basalt,demonstrate that these clinopyroxene phenocrysts were not captured crystals but were instead produced by crystallization differentiation of the magma.The calculated clinopyroxene crystallization temperatures showed a narrow range of 990-1061℃,and their crystallization pressures ranged from 2.0 to 3.2 kbar.The geochemistry features of these clinopyroxenes indicated that the parent magma belonged to the subalkaline tholeiitic magma series and suggested that the magma experienced crystallization differentiation of olivine,plagioclase,and clinopyroxene,where the crystallization of plagioclase occurred earlier than that of clinopyroxene.Combined with geophysical data,this research on primitive magma and its crystallization differentiation from clinopyroxene indicates that the SOT is in the stage of‘seafloor spreading’and that basaltic rocks produced from tholeiitic magma represent the generation of oceanic crust.

Deep Fractionation of Clinopyroxene in the East Pacific Rise 13°N:Evidence from High MgO MORB and Melt Inclusions

Mid-ocean ridge basalts （MORBs） from East Pacific Rise （EPR） 13°N are analysed for major and trace elements, both of which show a continuous evolving trend. Positive MgO-Al2O3 and negative MgO-Sc relationships manifest the cotectic crystallization of plagioclase and olivine, which exist with the presence of plagioclase and olivine phenocrysts and the absence of clinopyroxene phenoerysts. However, the fractionation of clinopyroxene is proven by the positive correlation of MgO and CaO. Thus, MORB samples are believed to show a “clinopyroxene paradox”. The highest magnesium-bearing MORB sample E13-3B （MGO=9.52%） is modelled for isobaric crystallization with COMAGMAT at different pressures. Observed CaO/Al2O3 ratios can be derived from E13-3B only by fractional crystallization at pressure 〉4±1 kbar, which necessitates clinopyroxene crystallization and is not consistent with cotectic crystallization of olivine plus plagioclase in the magma chamber （at pressure -1 kbar）. The initial compositions of the melt inclusions, which could represent potential parental magmas, are reconstructed by correcting for post-entrapment crystallization （PEC）. The simulated crystallization of initial melt inclusions also produce observed CaO/Al2O3 ratios only at 〉4±1 kbar, in which clinopyroxene takes part in crystallization. It is suggested that MORB magmas have experienced clinopyroxene fractionation in the lower crust, in and below the Moho transition zone. The MORB magmas have experienced transition from clinopyroxene＋plagioclase＋olivine crystallization at 〉4±1 kbar to mainly olivine＋plagioclase crystallization at 〈1 kbar, which contributes to the explanation of the “clinopyroxene paradox”.

Equilibrium between Clinopyroxene and Host Rocks:Implication for the Magmatic Source and Evolution of Alkali Basalts of the Taohekou Formation in the Northern Daba Mountains,China

The Taohekou Formation is a volcanic-sedimentary terrane formed in the early Silurian in the northern Daba Mountains, China. The volcanic rocks, with dominant alkali basalts and minor mantle xenoliths, are enriched in clinopyroxene phenocrysts. Geochemical analysis shows that the composition of clinopyroxenes from different lithofacies has a close affinity. There is a liner correlation present in composition of clinopyroxenes （including phenocryst, microcrystal and xenocryst） from coarse porphyritic basalts, pillow or fine porphyritic basalts to amygdaloidal basalts. All the cllnopyroxenes, except the clinopyroxenes in mantle xenoliths, show a similar pattern of trace elements and REE, which indicates that they are likely products of successive fractional crystallization from cognate magma. Clinopyroxenes in mantle xenoliths, however, are mantle xenocrysts. The crystallization pressure of clinopyroxenes gradually decreases from mantle xenolith, deep-seated xenocryst, coarse porphritic basalts, pillow or fine porphritic basalts, to amygdaloidal basalts, which are 1.92-4.41 GPa, 1.18-2.36 GPa, 1.13-2.05 GPa, 0.44-0.62 GPa and 0.14-0.28 GPa respectively. Calculation results suggest that the primary magma originated from a mantle region deeper than 68 km and stagnates in intervals of 37-68 kin, 15-20 km and 5-9 km during its ascent. The alkali basalts are characterized by increasing concentrations of Si and alkaline with the magmatic evolution. Meanwhile, they are markedly enriched in LREE, and the patterns of trace elements and REE are similar to those of oceanic island basalts.

Mantle melting beneath the Southwest Indian Ridge: signals from clinopyroxene in abyssal peridotites

The mineral chemistry and texture of clinopyroxenes in peridotite from the Kingkong tectonic zone of the Southwest Indian Ridge segment in an effort to constrain mantle melting beneath this slow-spreading ridge are reported. There are three types of clinopyroxenes in the abyssal peridotites： coarse-grained, intergranu- lar and exsolved. The compositional variations among these three types suggest that the coarse-grained clinopyroxene is a mantle-derived source. The A1, Na and Ti contents and the Na/Ti ratio of the coarse- grained clinopyroxene may be used to monitor the degree of partial melting, combined with the contradis- tinction with Spinel Cr#, which is calculated to be between 7.9% and 14.9%, and may represent low degrees of melting in the global ocean ridge system. The along-axis compositional variations in the coarse-grained clinopyroxene suggest that the degree of partial melting is primarily controlled by the transform faults on both sides of the ridge. Nonetheless, the northwestern side of the ridge may be affected by a hypothesised detachment fault as documented by the calculated P-T conditions. Simultaneously high Na and low Ti con- tents in the coarse-grained clinoovroxene points to mantle heterogeneities along the ridge axis.

Clinopyroxenes in Kimberlites of China

The author studied the grain size, shape, colour, altered coat, mineral species, chemical composition,end- member components and infrared spectra of clinopyroxenes occurring as megacryst, macrocryst andgroundmass minerals, intergrowths with pyrope and ilmenite and minerals in deep-seated xenoliths and inclu-sions in diamonds in kimberlites of China. The clinopyroxenes under study were compared with megacrystclinopyroxenes in basalts and minerals in their deep-seated xenoliths and clinopyroxenes in lamproites andminettes. The coexisting clinopyroxene-pyrope pair was studied. Besides the author also studied the origin ofclinopyroxenes in kimberlites, P-T conditions for their formation and their reflected tectonic environments ofthe kimberlite formation. He suggests that this mineral is an indicator for diamond exploration.

Monomineral universal clinopyroxene and garnet barometers for peridotitic,eclogitic and basaltic systems

New versions of the universal Jd-Di exchange clinopyroxene barometer for peridotites,pyroxenites and eclogites,and also garnet barometer for eclogites and peridotites were developed.They were checked using large experimental data sets for eciogitic（~530） and peridotitic systems（〉650）.The precision of the universal Cpx barometer for peridotites based on Jd-Di exchange is close to Cr-Tschermal

Oxidation Experiment of Natural Megacrystal Clinopyroxene:Implications for Assignment of Mssbauer Spectra

The M?ssbauer spectra of natural megacrystal clinopyroxene are usually fitted by 4 sets of symmetric doublets, A-A', B-B', C-C' and D-D', respectively, in terms of increasing Qs value in literature. But the assignments of those doublets are quite different, except the D-D' doublet assigned to Fe3+at the lattice site M***1 in previous papers. Particularly, the assignment and interpretation of the C-C' doublet are diverse.

M1 Site Splitting Due to Next Nearest Neighbor Effects and Ferric Iron in Tetrahedral Site in Clinopyroxene Megacrysts

It is well known that in pyroxene structure, there are two metal sites, M1 and M2.Generally speaking, ferrous iron in each of these sites would normally be expected to give rise to a doublet. However, anomies have been found in the relative areas of the peaks in the room temperature spectra of some clinopyroxene (CPX) when the above assigninent is folowed. Ac-cording to the calculation of Next Nearest Neighbor configurations of divalent cations in M1,we found that the four configurations of M1 can be divided into two groups. One group is 3Ca configuration that increases with the content of Ca (p. f. u); the other group is made up of three No-3Ca configurations that decrease with the content of Ca. The two groups contribute to the spectrum structure of M1, so in this study we fit two doublets for ferrous iron in M1.Though there were severa reports on Fe3+ in tetrahedral site previously, it wa not sure that Fe3+ occupies the T site is a universal fact in CPX, despite of the content of A1. We found that the Fe3+ in the T site fitted by Medauer spectroscopy is negatively correlated to the Si content in the T site and positively correlated to the Fe3 + in the T site estimated on the suppo-sition that Fe3+ and Al occupy the T site randomly. If it is true, it is important in the model-ing of ion exchange geobarometries and gepthermornetries.

Ediacarian Volcanic Rocks and Basic Dikes from the Lac Ifni Sector of the Central High Atlas Mountains:Petrographic Studies and Clinopyroxene Chemical Composition

The Ediacarian volcanic series from the Lac Ifni sector are composed of a large variety of rocks from basalts and rhyolites to intermediates facies such as andesites,rhyodacites and pyroclastites.All these rocks are intruded by dolerite dikes.Secondary processes are reflected by total serpentinization of olivine within basic andesite and by albitization

内蒙朝克山辉长岩中单斜辉石矿物化学特征及地质意义

内蒙贺根山带广泛发育古生代基性岩浆岩,为探讨其岩浆源区和岩石成因,进一步了解中亚造山带东段古生代构造背景,笔者对朝克山蛇绿岩进行了矿物学研究。矿物电子探针结果显示,辉长岩中单斜辉石均属于透辉石,既有碱性特征,也有拉斑特征,SiO2含量为50.75%~52.99%,具有高的Al2O3,含量为2.03%~3.77%,相对亏损轻稀土元素(La/Sm)_(N)=0.12~0.22和高场强元素(HFSE;Nb、Ta、Zr、Hf、Ti负异常),富集大离子亲石元素(LILEs),与辉长岩全岩的特征程度相一致,共同指示岩体母岩浆可能为亚碱性的拉斑玄武质岩浆向碱性玄武质岩浆演化的趋势。单斜辉石的平衡温度为1099~1242℃,平衡压力为1.5~6.4 kbar,深度为5~21 km,显示明显的深源特征。结合前人研究成果,笔者认为朝克山蛇绿岩形成于弧后盆地环境。

1例复杂重组HIV-1亚型(CRF09-cpx)的鉴定

目的鉴定我国首例报道的复杂重组HIV-1(CRF09-cpx)感染病例,回顾性观察其抗病毒治疗的效果及耐药性的产生。方法分别采用蛋白酶基因、反转录酶基因以及env基因片段进行HIV-1的亚型分析;采用Trugene HIV-1基因型检测系统进行HIV-1基因型耐药检测。结果患者所感染的毒株与CRF09复杂重组毒株亲缘关系最为密切;在治疗过程中出现了耐药相关的位点突变并导致对多种药物产生耐受,同时表现出了耐药位点的累积。结论鉴定了我国首例报道的CRF09复杂重组HIV-1毒株并初步分析其耐药特征。

Hot subduction in the southern Paleo-Asian Ocean:Insights from clinopyroxene chemistry and Sr-Nd-Hf-Pb isotopes of Carboniferous volcanics in West Junggar

The chemical evolution and pressure-temperature conditions of subduction zone magmatism along ancient suture zones in orogenic belts can provide important information regarding plate convergence processes in paleo-oceans.Carboniferous magmatism in West Junggar is key to understanding the tectonothermal and subduction history of the Junggar Ocean,which was a branch of the Paleo-Asian Ocean,as well as the accretionary processes in the southwestern Central Asian Orogenic Belt(CAOB).We undertook a geochronological,mineralogical,geochemical,and Sr-Nd-Hf-Pb isotopic study of volcanic rocks from the Baikouquan area of West Junggar.We used these data to determine the petrogenesis,mantle source,and pressure-temperature conditions of these magmas,and further constrain the subduction and tectonic history of the Junggar Ocean.The studied volcanic rocks yielded zircon U-Pb ages of 342-337 Ma and are characterized by enrichments of large-ion lithophile elements(LILEs),and depletions in high-field-strength elements(HFSEs),indicative of an island arc affinity.The volcanic rocks have positiveƐNd(t)(5.83-7.04)andƐHf(t)(13.47-15.74)values,87Sr/86Sr(t)ratios of 0.704023-0.705658,and radiogenic 207Pb/204Pb(t)and 208Pb/204Pb(t)ratios at a given 206Pb/204Pb(t)ratio,indicative of a depleted mantle source contaminated by subduction-related materials.Geochemical modeling calculations indicate that≤1%of a subduction component comprising fluid and sediment melt could have generated the source of the parental melts of the Baikouquan volcanic rocks.Clinopyroxene phenocrysts in the volcanic rocks are classified as high-and low-Ti clinopyroxene,and pressure-temperature calculations suggest the host rocks formed at high temperatures(~1300℃)and shallow to moderate depths(<2 GPa).The magma was probably generated by hot and hydrous melting in a mantle wedge in response to subduction of young,hot oceanic lithosphere.The present results,combined with published data,suggest that the Baikouquan volcanic rocks record a transition in tectonic setting from normal cold to anomalous hot subduction of young oceanic lithosphere close to a mid-ocean ridge.This indicates ridge subduction began shortly after 337 Ma.Our results provide new insights into the tectonomagmatic evolution during intra-oceanic subduction prior to ridge subduction.

柑橘降产能、提品质、增效益生产模式管理技术路径探讨

柑橘是我国南方地区主栽的果树种类。发展柑橘产业可促进农村经济发展、增加农民收入、帮助农民实现脱贫致富,在乡村经济建设中发挥着重要作用。近年来,我国各柑橘主产区大力推动柑橘产业发展,使柑橘种植面积不断扩大,产量不断提高,但也存在因追求高产而过量挂果、过量使用化肥农药的现象,导致出现柑橘量高质劣、销售困难、效益不好等问题。为解决这些问题,从定果降产、减肥增效、节水控量、促色保形、减药绿防等五个方面进行研究,并提出柑橘降产能、提品质、增效益(CPX)生产模式管理技术路径。

Cpx对迟缓爱德华氏菌毒力的影响

迟缓爱德华氏菌(Edwardsiella tarda)是水产养殖动物常见病原菌。接合质粒表达系统(conjugativeplasmid expression,Cpx)是G–菌的双组分调控系统。本研究构建了迟缓爱德华氏菌LSE40的cpx基因簇缺失突变株Δcpx,检测其对蓝曼龙(Trichogaster trichopterus)的毒力。结果显示以浸泡感染,Δcpx的毒力有所降低。以肌肉注射途径感染,Δcpx的半数致死量为8.6×105cfu/mL毒力下降7.33倍。Δcpx在鱼体内的生存力显著下降(P<0.05)。这些结果表明Cpx参与了迟缓爱德华氏菌的致病作用。

细菌Cpx信号转导系统的功能及调控机制研究进展

Cpx(conjugative pilus expression)双组分信号转导系统是革兰阴性细菌中一种复杂的包膜应激系统,能感应从不同信号传输点传入的多种包膜信号。位于胞质中的反应调节子CpxR磷酸化后能够调节众多编码内外膜上相关蛋白基因的表达。Cpx系统的激活还能调节细菌对抗生素和酸等压力的抵抗性。本文介绍了Cpx系统的组成,重点对Cpx系统的信号感应及调控机制进行综述,以期为Cpx系统的调控网络及其调节细菌重要生理过程的研究提供参考依据。

利用环境空气及路面温度对近距轮胎/路面噪音测量法(CPX)的修正(英文)

一般在公路上进行CPX轮胎/路面噪音测量时,环境温度对测量的影响往往是不易受控制的。研究人员们已针对此问题开发出一温度修正方法,透过不同的温度参数以补偿温度对量度得出的噪音水平之影响。本研究试图以一整天的CPX测量结果,以探索测试时使用环境气温和路面温度为本的修正及其可靠性,同时并得出两种路面上的温度修正值。

CPX终端阀岛在自动化生产实训台中的应用

气动控制部分在传统的自动化生产线实训台中通常采用各独立的气动控制阀类元件来对执行机构动作进行控制,其安装技术要求高,控制线多而复杂,要求安装空间较大,实训台控制方式单一,综合性差。针对这些问题,本文提出了1种基于现场总线的CPX终端阀岛,来替代传统的多个单一的气动控制阀元件,同时采用西门子S7-300可编程控制器(PLC)来控制整个系统运行过程。实验表明该方法能提高控制精度,节省安装空间,减少控制线,提高实训台的综合性能。

一株HIV-1 CRF65-cpx新型重组毒株的检出及基因重组序列分析

目的对广西边境某市1例经异性接触感染HIV-1的患者血清样本进行近全长基因组序列扩增和分析,以期了解其重组模式和基因序列的特征。方法采用RT-PCR和巢式PCR方法,对研究对象血清样本的病毒RNA进行逆转录、扩增、测序,分析基因重组断点并确认重组模式,并构建亚型系统进化树。结果测序结果显示,毒株序列全长为8900 bp,是以C为骨架,插入CRF01-AE和B亚型片段组成的CRF65-cpx重组亚型(B/C/CRF01-AE)毒株。耐药分析结果显示,该基因序列毒株存在V179D耐药突变。该重组毒株近全长基因序列由CRF01-AE、B和C组成,序列位置为790~9412bp,含14个片段,其13个断点位置为1170、3803、4015、5655、5830、5993、6378、7586、8349、8506、8568、8830和8995,片段Ⅰ、Ⅴ、Ⅶ、Ⅹ和Ⅻ为CRF01-AE亚型,片段Ⅲ、Ⅵ、Ⅸ和ⅩⅢ为B亚型,片段Ⅱ、Ⅳ、Ⅷ、Ⅺ和ⅩⅣ为C亚型。结论在广西边境某市发现的CRF65-cpx毒株是由B、C和CRF01-AE亚型毒株重组而成,且含有V179D突变。广西边境地区应加强对该亚型或者类似新型毒株的监测并采取相应的预防控制措施,以防止境外新型重组毒株或本地重组毒株在该地区的扩散传播流行。

CPX200交换机总体技术特点介绍与分析

本文对DELTAMOBILECPX200多功能战术交换机总体指标进行了详细的介绍,对其总体技术特点进行了分析,并结合我国目前战术通信设备现状,提出战术通信网中交换设备的改进方向。

CPX⁃351对比“7+3”化疗在初诊高危或继发性急性髓系白血病老年患者中的5年随访结果

1文献来源Lancet JE,Uy GL,Newell LF,et al.CPX⁃351 versus 7+3 cytarabine and daunorubicin chemotherapy in older adults with newly diagnosed high⁃risk or secondary acute myeloid leukaemia:5⁃year results of a randomised,open⁃label,multicentre,phase 3 trial[J].Lancet Haematol,2021,8(7):e481-e491.2证据水平1b。3背景柔红霉素和阿糖胞苷被作为急性髓系白血病(acute myeloid leukaemia,AML)患者的标准诱导化疗。CPX⁃351是柔红霉素和阿糖胞苷协同包封的双药脂质体(摩尔比1∶5)。