Geochemistry of the Aptian bituminous limestones in Gümuü?hane area,Eastern Black Sea region:new insight into paleogeography and paleoclimate conditions

Aptian is characterized by widespread deposition of organic-rich sediment.The Aptian bitumen limestone horizon,which is thin decimetre-thick sequences,locally crops out in the Kircaova area,Eastern Black Sea Region(Eastern Pontides).They are well correlated with Aptian bitumen limestone in the other Tethys Reams.They are proposed as episodes of increased organic matter.However,background factors controlling organic matter enrichment are poorly known.In this study,we present new inorganic geochemistry,including trace elements,rare earth elements(REE),redox-sensitive elements(RSE),stable-isotopes(δ~(18)O andδ~(13)C),and total organic carbon(TOC).We integrated new geochemical data with existing stratigraphy,paleontology,and organic chemistry data to provide new insight into the depositional environment and paleoclimate conditions during Aptian.The lacustrine bitumen limestone(LBL)samples have variedδ~(13)C(ave.-1.45‰)andδ~(18)O(ave.-4.50‰).They possess distinct REE patterns,with an average of REE(ave.14.45 ppm)and Y/Ho(ave.35)ratios.In addition,they have variable Nd/YbN(0.28-0.81;ave.0.56)and Ce/Ce*(0.68-0.97;ave.0.86),and relatively high Eu^(*)/Eu(1.23-1.53;ave.1.35).They display seawater signatures with reduced oxygen conditions.The enrichment in RSE(Mo,Cu,Ni,and Zn)and the low Mo/TOC(0.70-3.69;ave.2.41)support a certain degree of water restriction.The high Sr/Ba,Sr/Cu,Ga/Rb,and K/Al records of the LBL facies suggest hot house climatic conditions.The sedimentary environment was probably an isolated basin that is transformed from the marine basin.In addition to depositional conditions,the regional parameters such as the climate,increased run-off period,nutrient levels,alkalinity level,and dominant carbonate producers favored the enrichment in organic matter of LBL facies.Thus,extreme greenhouse palaeoclimate conditions have an important role in organic matter enrichment in the isolated basin.Our results are conformable with the published data from marine,semi-restricted basin,and lacustrine settings in the different parts of the Tethys margin.Thus,this approach provides the first insight into the Aptian greenhouse paleo-climate conditions of the Eastern Black Sea Region,NE Turkey.

冷弯薄壁卷边C形不锈钢梁的力学性能试验

为了研究冷弯壁薄卷边C形钢受弯构件的力学性能,以冷弯薄壁不锈钢梁为研究对象,重点研究加载条件、跨度对构件屈曲模式和受弯承载力的影响。结果发现:试件的加载条件和跨度对冷弯薄壁卷边C形钢受弯构件屈曲模式和极限承载力的影响显著,纯弯加载下的短梁极限承载力高达169.1 kN,破坏模式为畸变屈曲,其余试件破坏模式也为畸变屈曲;腹板V型加劲能够有效抑制腹板鼓曲的产生,提高试件的极限承载力。利用现有直接强度法修正公式的计算结果与试验结果进行对比,以验证公式的准确性。

Effects of UV-B radiation and different light repair conditions on the early development of the tetraspores of Chondrus ocellatus Holm

The effects of exposure to UV-B radiation, 280-315 nm, and dark or dark repair conditions on the early development of Chondrus ocellatus Holm collected from Qingdao coast were studied under the laboratory condition. After being exposed to different doses [0, 36, 72, 108, 144 and 180 J/（m2.d）] of UV-B radiation, one treatment of tetraspores were put back to normal culture condition （PAR）, the other treatment were put into dark condition to repair for 2 h. During the cultivation, the diameter of the tetraspores were recorded every 4 d till the 50th day when vertical branches formed in all treatments. Then at the 50th day, CPDs, phycoerythrin, chlorophyll a and MAAs （Palythine and asterina-330） were measured. The results showed that low doses UV-B radiation could significantly accelerate the growth rate of the rate reduced gradually with UV-B radiation keep on tetraspores of C. ocellatus and the growth increasing. The variation trend of both the phycoerythrin and chlorophyll a concentration reduced significantly （P 〈0.05） once given the UV- B radiation. Under UV-B stress, the CPDs were induced, and the concentrations of CPDs were significant low in dark repair groups. The data of MAAs analyzed by LC/MS in the tetraspores of C. ocellatus suggested that there were two MAAs formed （palythine and asterina-330） after UV-B radiation induced, and low dose of UV-B irradiation could significantly induced the concentration of MAAs. From the growth and development state of the tetraspores, negative effects of UV-B radiation on the dark repair groups were more serious than PAR.

EFFECT OF DEPOSITIONS CONDITION ON THE MICROSTRUCTURE OF C/C MINICOMPOSITE

C/C minicomposites were manufactured by CVI with propylene as resource gas and Ar as diluent gas. Effects of deposition temperature, the flow rate of propylene and total system pressure on the microstructure of C/C minicomposites were investigated. Deposition conditions are as follows: deposition temperature ranging from 870℃ to 1000℃, the flow rate of propylene from 10 to 60 ml/min, and total system pressure from 3 to 16kPa. The results revealed: The deposit distributes non uniformly as increasing the deposition temperature or total system pressure. The effect of the flow rate of propylene on the distribution of deposit observes different principles at different deposition temperatures. If the deposition temperature rises to 900℃, the deposit distributes more non uniformly as increasing the flow rate of propylene. The morphology of deposit varies with deposition condition, such as smooth, droplet like or spike like. Deposition mechanism varies with deposition condition. It can be surface reaction nucleation and growth, heterogeneous nucleation of liquid droplet on carbon fiber or gas borne nuclei growth. With the principle of nuclei growth of crystal and the method of phenomenology, the changes of deposition mechanism and the morphology of pyrolytic carbon with deposition condition were explained successfully. The effect of deposition condition on deposit homogeneity stems from the effect of deposition condition on the CVI kinetics and the deposition mechanism of pyrolytic carbon.

Tribological characteristics of C/C-SiC braking composites under dry and wet conditions

C/C-SiC braking composites,based on reinforcement of carbon fibers and matrices of carbon and silicon carbide,were fabricated by warm compaction and in situ reaction process.The tribological characteristics of C/C-SiC braking composites under dry and wet conditions were investigated by means of MM-1000 type of friction testing machine.The influence of dry and wet conditions on the tribological characteristics of the C/C-SiC composites was ascertained.Under dry condition,C/C-SiC braking composites show superior tribological characteristics,including high coefficient of friction (0.38),good abrasive resistance (thickness loss is 1.10 μm per cycle) and steady breaking.The main wear mechanism is plastic deformation and abrasion caused by plough.Under wet condition,frictional films form on the worn surface.The coefficient of friction (0.35) could maintain mostly,and the thickness loss (0.70 μm per cycle) reduces to a certain extent.Furthermore,braking curves are steady and adhesion and oxidation are the main wear mechanisms.

Leptin receptor of the hind brain nuclei is involved in the conditioned taste preference of rats

Objective: Conditioned taste preference(CTP) is a taste learning reflex by which an animal learns to prefer a substance which tastes not well and has been studied with much interest in recent years. However, the neural substrates of CTP are less known. This study aimed to determine the possible neural pathways of CTP and whether serum leptin level and the leptin receptor(OB-Rb) in the hind brain are involved following CTP formation. Methods: We established CTP of quinine in rats with a 2-bottle preference test. The serum leptin concentrations were detected, the expression of c-fos in the rat brain was tested to determine the nuclei in relation with establishment of CTP. Finally, the OB-Rb m RNA expression was examined by RT-q PCR assay in parabrachial nucleus(PBN) and the nucleus of the solitary tract(NST) of the hind brain. Results: Compared with control group, the level of serum leptin was higher in the CTP group(4.58 ± 0.52 vs 1.67 ± 0.25 μg/L, P<0. 01); increased c-fos positive cells were found in the anterior hypothalamus(AH, 221.75 ± 4.96 vs. 178.50±6.63 cells/mm^2, P<0.05), the basal lateral amygdala(BLA, 70.75±6.17 vs 56.50±3.62 cells/mm^2, P<0.05) and the nucleus of the solitary tract(NST, 41.25±1.32 vs 32.50±1.02 cells/mm^2, P<0.05). But in ventromedial nucleus of the hypothalamus(VMH, 20.75±2.73 vs 38.5±1.54 per 1 mm^2, P<005), PBN(21.50 ±2.24 vs 36.25±1.49 cells/mm^2, P<0.05) and the central nucleus of the amygdala(Ce A, 22.25±1.53 vs 35.50 ±2.11 cells/mm^2, P<0.05), the number of c-fos positive cells was decreased in the CTP group. In addition, we found OB-Rb m RNA expression in PBN of CTP group rats was higher than that of control group(0.95±0.055 vs 0.57± 0.034, P<0.05), while there was no significant difference of OB-Rb m RNA expression in NST between the two groups. Conclusion: Nuclei AH, BLA, NST, VMH, PBN and Ce A participate in the formation of CTP. Leptin and its receptor in PBN may be involved in the formation and maintenance of CTP.

基于VMD和FCM的火箭发动机涡轮泵状态监测方法

面向重复使用火箭发动机的状态监测与故障诊断需求,针对振动信号的非平稳性和难以提取有效故障特征的问题,提出一种基于变分模态分解(Variational Mode Decomposition, VMD)和模糊C均值聚类(Fuzzy C-Means, FCM)的状态监测方法。采用优化VMD算法自适应地将振动信号分解为多个本征模态分量(Intrinsic Mode Function, IMF),根据加权相关样本熵最大准则选取关键IMF分量;利用t分布随机近邻嵌入(t-SNE)对关键IMF分量的多维时域、频域特征降维,得到特征向量矩阵;利用模糊C均值聚类算法实现发动机工作状态的监测。将该方法应用于发动机涡轮泵工作状态监测,结果表明其能够提取振动信号关键特征,准确识别涡轮泵工作状态,测试集识别准确率达92.50%,为火箭发动机状态监测与故障诊断提供了理论支撑。

原发性膝骨关节炎患者CRP/PAB比值与病情严重性、发病的关系

目的 探讨原发性膝骨关节炎(KOA)患者C反应蛋白/前清蛋白(CRP/PAB)比值与病情严重性、发病的关系。方法 选取2021年2月至2023年1月海南西部中心医院收治的93例原发性KOA患者作为本次研究对象(KOA组),根据Kellgren-Lawrence(KL)分级将患者分为轻中度组66例(KL分级1~3级)、重度组27例(KL分级4级)。另外选取同时期来本院进行体检的130名健康人作为对照组。比较KOA组与对照组、KOA患者轻中度组与重度组血清CRP、PAB水平及CRP/PAB比值情况;采用受试者工作特性(ROC)曲线评估CRP、PAB、CRP/PAB比值对原发性KOA患者病情的预测价值;采用二分类Logistic逐步回归分析探讨原发性KOA患者发病的影响因素。结果 KOA组血清CRP水平和CRP/PAB比值高于对照组,PAB水平低于对照组,差异有统计学意义(P<0.05)。重度组血清CRP水平和CRP/PAB比值高于轻中度组,PAB水平低于轻中度组,差异有统计学意义(P<0.05)。CRP、PAB、CRP/PAB比值预测原发性KOA患者病情的曲线下面积(AUC)分别为0.849(0.797~0.901)、0.751(0.699~0.803)、0.903(0.851~0.955),截点值分别为52.55 mg/L、172.77 mg/L、0.37,特异度分别为0.680、0.571、0.870,灵敏度分别为0.913、0.913、0.845。二分类Logistic逐步回归分析显示,高龄(OR=2.368,95%CI:1.584~3.539)、有KOA家族史(OR=2.158,95%CI:1.475~3.156)、CRP/PAB比值≥0.37(OR=2.782,95%CI:1.797~4.306)是原发性KOA患者发病的独立危险因素(P<0.05)。结论 血清CRP/PAB比值升高与原发性KOA的发病和病情严重程度密切相关,可作为预测原发性KOA患者病情的潜在生物标记物,有一定的临床应用价值。

Fourth-Order Compact Formulation for the Resolution of Heat Transfer in Natural Convection of Water-Cu Nanofluid in a Square Cavity with a Sinusoidal Boundary Thermal Condition

In the present work, we numerically study the laminar natural convection of a nanofluid confined in a square cavity. The vertical walls are assumed to be insulated, non-conducting, and impermeable to mass transfer. The horizontal walls are differentially heated, and the low is maintained at hot condition (sinusoidal) when the high one is cold. The objective of this work is to develop a new height accurate method for solving heat transfer equations. The new method is a Fourth Order Compact (F.O.C). This work aims to show the interest of the method and understand the effect of the presence of nanofluids in closed square systems on the natural convection mechanism. The numerical simulations are performed for Prandtl number ( ), the Rayleigh numbers varying between and for different volume fractions varies between 0% and 10% for the nanofluid (water + Cu).

^(60)CO-r射线辐射辣椒(甜椒)种子诱变效应研究

采用60CO-r射线1-5万伦琴对辣椒(甜椒)种子进行辐射处理,结果表明:对辣椒(甜椒)品种之间发芽率和出苗率影响很大,随着辐射剂量增加,辣椒(甜椒)的发芽率和出苗率逐渐降低。辣椒在1万伦琴低剂量处理,辣椒植株茎粗、茎高、地上部鲜重与对照差别不大,个别植株有所增加,但变异频率很低。当剂量增加,出苗率降低,变异频率增加;在4万伦琴的剂量以上,处于半致死剂量;最适宜的辐射剂量2万伦琴。甜椒在3万伦琴的剂量以上,处于半致死剂量;最适宜的辐射剂量1.5-2万伦琴。

EG7564C-RS点阵液晶的开发应用

介绍了EPSONEG7564C-RS点阵液晶和Motorola16位单片机MC68HC16Z1的硬件连接电路以及在该液晶上的画点程序和图片显示程序。该程序可以在液晶任意位置上显示任意字符、图片,其设计方案可应用于各种选用点阵液晶显示的微型仪器的界面设计中。

复变函数中C.-R方程的教学过程分析

在复变函数中,C.-R.V方程,即柯西-黎曼方程是讨论函数解析性的核心内容,也是研究柯西积分定理的基础,本文针对实际教学中学生的学习情况对C.-R.方程的教学过程做了进一步分析与优化。

维生素C及衍生物的稳定性分析

本研究分析了光照、空气、温度和储藏时间对市场上8种常见维生素C原料稳定性的影响。结果表明,8种维生素C在日光、紫外光照射及避光条件下6 h后保留率在95%左右;在密封条件下加热处理时,维生素C的降解较慢,而当样品与空气接触时,其降解加快,随温度增高而加快;在有氧条件下,当温度升高至50℃及以上时,所有样品降解明显。比较热及储藏稳定性发现,乙基醚维生素C具有最高的稳定性,维生素C、100目维生素C、复配维生素C和96%颗粒维生素C次之,维生素C钠、复配维生素C钠和维生素C钙具有最低的热和储藏稳定性。研究结果将为果蔬保鲜及和维生素C稳定化提供理论参考。

C.-R.方程的推广及其应用

利用多元函数方向导数的概念与矩阵变换等方法推广了C.-R.方程,给出了解析函数f(z)=u(x,y)+iv(x,y)的实部与虚部关于任意两个方向v1,v2的方向导数(v/u1,v/v1)与(v/u2,v/v2)之间的关系.利用所得结果对复变函数可微的一个充要条件做了改进.相应的结论对解析函数也成立.

JONES TYPE C^(*)-BASIC CONSTRUCTION IN NON-EQUILIBRIUM HOPF SPIN MODELS

Let H be a finite dimensional Hopf C^(*)-algebra,and let K be a Hopf^(*)-subalgebra of H.Considering that the field algebra■K of a non-equilibrium Hopf spin model carries a D(H,K)-invariant subalgebra ■K,this paper shows that the C^(*)-basic construction for the inclusion ■K×■K can be expressed as the crossed product C^(*)-algebra■KD(H,K).Here,D(H,K)is a bicrossed product of the opposite dual H^(op) and K.Furthermore,the natural action of D(H,K)on D(H,K)gives rise to the iterated crossed product■KD(H,K)×D(H,K),which coincides with the C^(*)-basic construction for the inclusion■K×■KD(H,K).In the end,the Jones type tower of field algebra■Kis obtained,and the new field algebra emerges exactly as the iterated crossed product.

科尔维特看你到底有多狂——参加勒芒耐力赛的雪佛兰科尔维特C5-R

勒芒的赛车是以道路车为基础的,所以C5-R保留着许多原产车的配置,如发动机的缸体。但通过对缸内部分的改造,C5-R已经不再是适于普通人开上马路的普通跑车了。它现在的发动机缸径加大(从99毫米增加到105毫米)。

C/SiC编织型复合材料热/力学性能的多尺度预测

C/SiC复合材料以其优异的力学和热学性能,在航空航天、国防和化学工业等领域都得到了广泛的应用.精准获得C/SiC复合材料的热/力学性能,对该类材料在相关领域的高效应用至关重要.基于代表性体积单元(RVE)和周期性边界条件,考虑纤维束的体积分数、交织方式、编织维度等非均匀、多尺度特征,建立了C/SiC复合材料的微/细观单胞模型.使用有限元软件ABAQUS在微观尺度预测了纤维束的热/力学性能,将纤维束性能引入细观模型中,分析获得了该复合材料的宏观热/力学性能.基于此多尺度关联分析方法,在27~1227℃的工作温度范围内,进一步研究了纤维束和C/SiC复合材料的热导率和热膨胀系数随温度的变化规律.该研究对C/SiC复合材料在工程上的应用具有一定的指导意义.

血清C反应蛋白、白细胞介素-6和胃泌素-17水平与腹型过敏性紫癜患儿病情严重程度的相关性

目的:观察血清C反应蛋白(CRP)、白细胞介素-6(IL-6)和胃泌素-17(G-17)水平与腹型过敏性紫癜(HSP)患儿病情严重程度的相关性。方法:选取2019年1月至2021年1月该院收治的80例腹型HSP患儿,设为观察组,根据病情严重程度不同将其分为轻度组(n=26)、中度组(n=35)和重度组(n=19)。另取同期80名体检健康儿童为对照组,比较两组血清CRP、IL-6和G-17水平,并分析血清CRP、IL-6和G-17水平与腹型HSP患儿病情严重程度的相关性。结果:观察组血清CRP、IL-6水平均高于对照组,血清G-17水平低于对照组,差异有统计学意义(P<0.05);不同病情程度患儿血清CRP、IL-6水平比较,重度组>中度组>轻度组,差异均有统计学意义(P<0.05);不同病情严重程度患儿血清G-17水平比较,重度组<中度组<轻度组,差异均有统计学意义(P<0.05);Pearson相关性分析结果显示,血清CRP、IL-6水平与腹型HSP患儿病情程度呈正相关(r>0,P<0.05),血清G-17水平与腹型HSP患儿病情严重程度呈负相关(r<0,P<0.05)。结论:血清CRP、IL-6水平与腹型HSP患儿病情严重程度呈正相关,血清G-17水平与腹型HSP患儿病情严重程度呈负相关。

ACS患者PCI后1年内再狭窄与TYG指数、CysC、CRP水平的关系及影响因素分析

目的分析急性冠状动脉综合征(ACS)患者经皮冠状动脉介入治疗(PCI)后1年内再狭窄与血清甘油三酯与葡萄糖乘积(TyG)指数、胱抑素C(CysC)、C反应蛋白(CRP)水平的关系及影响因素。方法回顾性选取2020年5月至2022年3月巴中市中心医院收治的108例行PCI的ACS患者,术后1年返院复查冠脉造影,根据造影复查结果将患者分为再狭窄组(n=29)和非再狭窄组(n=79)。比较两组患者一般临床资料、TYG指数、CysC、CRP水平、支架情况。采用多因素Logistic回归分析分析影响ACS患者PCI术后1年内支架内再狭窄的因素。结果再狭窄组患者不稳定型心绞痛比例为17.24%,低于非再狭窄组(43.04%),非ST段抬高型心肌梗死、ST段抬高型心肌梗死比例分别为55.17%、27.59%,高于非再狭窄组(31.65%、25.32%),差异均有统计学意义(P<0.05)。再狭窄组的HDL-C水平为(1.27±0.28)mmoL/L,低于非再狭窄组[(1.42±0.31)mmoL/L],术前狭窄程度、TYG指数、CysC、CRP水平分别为(94.31±5.01)%、7.40±0.38、(1.41±0.32)mg/L、(36.58±3.41)mg/L,高于非再狭窄组[(83.24±3.38)%、6.14±0.32、(1.14±0.31)mg/L、(19.42±2.78)mg/L],差异均有统计学意义(P<0.05)。再狭窄组的支架直径≥3 mm比例为27.59%,低于非再狭窄组(72.15%),术后残余狭窄率为(5.96±1.25)%,高于非再狭窄组[(3.74±0.86)%],差异均有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,支架直径≥3 mm是ACS患者PCI术后1年内支架内再狭窄的保护因素(P<0.05),术前狭窄程度、诊断分型、TYG指数、CysC、CRP是ACS患者PCI术后1年内支架内再狭窄的独立危险因素(P<0.05)。结论PCI后1年内再狭窄ACS患者TYG指数、CysC、CRP水平升高,TYG指数、CysC、CRP是ACS患者PCI后1年内再狭窄的独立危险因素。

C-RAN机房过热问题分析及改造方案应用

针对5G时代基于云计算的无线接入网构架(Cloud-Radio Access Network,C-RAN)机房的建设现状和过热问题,分析了设备过热原因和解决思路。基于5G设备的供冷需求,提出了一种新的机柜级制冷方案。通过与实际工程应用进行对比分析,该方案可以有效解决机房过热问题,降低运营成本和空调能耗,同时满足可持续的节能发展需求。