面向港口复杂装卸系统的动态机会维护策略

针对以不同衰退特征设备组成的港口复杂装卸系统,提出了设备层-系统层交互的动态机会维护策略,以支撑自动化码头的智能维护决策.引入维护效果和外部环境工况,提出了独立设备的综合衰退演化规则,并结合多目标价值理论和动态循环决策模式,建立设备层多目标预知维护规划模型.在此基础上,分析串联设备间的相互依赖性,利用设备停机的组合维护机会,建立了多设备维护优化调度的联合区间轴策略,对关联设备的预知维护作业采取有针对性的作业合并.数值实例结果证明,所提出的方法可显著降低系统整体维护成本,提供具有可行性、实时性、经济性的系统层维护优化方案.     

三峡库区二道河滑坡变形机制研究

受三峡水库蓄水影响,二道河滑坡出现了变形加剧现象。通过监测数据分析和蓄水过程中滑坡渗流及稳定性数值模拟,分析了滑坡的变形演化过程及变形机制。结果表明:二道河滑坡从开始变形到三峡水库不同阶段蓄水的过程中,经历了由推移式转化为牵引式、由悬浮减重型转化为动水压力滞后型的过程,滑坡变形的地质力学模式为蠕滑—拉裂型。对滑坡变形机制转化的分析可供类似滑坡的分析研究参考。     

Precise orbit determination for geostationary satellites with multiple tracking techniques

A new precise orbit determination (POD) strategy based on the combination of satellite laser ranging (SLR) and C-band transfer ranging for geostationary satellites (GEO) is presented.Two approaches to calibrate ranging biases of the C-band ranging system are proposed,namely the two tracking system co-location comparison and the combined POD method,with calibration accuracies estimated to be 0.5 ns and 1 ns respectively.Using data from a C-band tracking network in China,POD experiments indicate that meter-le...     

自动信任协商安全性的形式化分析与验证

为了对自动信任协商(ATN)的安全性进行形式化分析与验证,文中借鉴安全协议的形式化分析方法,提出一种用进程代数Applied π演算对ATN建模并验证其安全性的方法.该方法将ATN形式化为两个协商者进程的并发执行,其中一个协商者的进程就是对其拥有的证书及授权策略的静态建模;ATN的安全性被定义为Applied π演算的观察等价性,从而使该方法不仅能检查授权策略执行的安全性,而且能对协商者的隐私安全进行验证.借助安全协议的自动分析工具ProVerif,文中实现了对ATN安全性的自动分析.实验结果表明,用Applied π演算形式化及验证ATN的安全性是可行的,安全性验证可自动完成,并且效率较高.     

Sinorhizobium meliloti lsrB is involved in alfalfa root nodule development and nitrogen-fixing bacteroid differentiation

Rhizobia interact with host legumes to induce the formation of nitrogen-fixing nodules, which is very important in agriculture and ecology. The development of nitrogen-fixing nodules is stringently regulated by host plants and rhizobial symbionts. In our previous work, a new Sinorhizobium meliloti LysR regulator gene (lsrB) was identified to be essential for alfalfa nodulation. However, how this gene is involved in alfalfa nodulation was not yet understood. Here, we found that this gene was associated with prevention of premature nodule senescence and abortive bacteroid formation. Heterogeneous deficient alfalfa root nodules were induced by the in-frame deletion mutant of lsrB (lsrB1-2), which was similar to the plasmid-insertion mutant, lsrB1. Irregular senescence zones earlier appeared in these nodules where bacteroid differentiation was blocked at different stages from microscopy observations. Interestingly, oxidative bursts were observed in these nodules by DAB staining. The decreased expression of lipopolysaccharide core genes (lpsCDE) was correspondingly determined in these nodules. S. meliloti lipopolysaccharide is required for suppression of oxidative bursts or host cell defense. These findings demonstrate that the S. meliloti lsrB gene is involved in alfalfa root nodule development and bacteroid differentiation by suppressing oxidative bursts or defense responses in host cells.     

Optical detection of acetylcholine esterase based on CdTe quantum dots

In this study, we have constructed a simple, sensitive and rapid biosensor for detection of acetylcholine esterase (AChE) based on CdTe quantum dots (QDs). The detection limit of AChE by one-step enzyme reaction based on the thiolglycolic acid (TGA) stabilized QDs (TGA-QDs) was 10 U/L and the linear range was 10-100 and 100-1200 U/L, respectively. The detection limit of AChE by two-step enzyme reaction based on the 3-mercaptopropionic acid (MGA) stabilized QDs (MGA-QDs) was found to be 20 U/L and the linear range was 100-2500 U/L. The experimental conditions of biosensors were optimized, and the detection mechanism was studied. We also detected AChE in serum samples based on TGA-QDs or MGA-QDs. The linear range was 10-140 and 50-1000 U/L, respectively. The excellent performance of this novel biosensor demonstrated that this strategy has prodigious potential to be applied in practice detection of AChE.     

Observational evidences for the speed of the gravity based on the Earth tide

We have found that the current practical Newtonian formula for the gravity tide of the Earth implies a hypothesis that gravity travels at the speed of light; furthermore, we have derived and solved the propagation equation of gravity using the observation data of Earth tides from Shiquanhe and Wushi, after correction of phase lag due to the anelasticity of the Earth, and found that the speeds of gravity are from 0.93 to 1.05 times the speed of light with a relative error of about 5%. This provides first set of strong evidences to show that the speed of gravity is the same as the speed of light.     

High efficiency D-A structured luminogen with aggregation-induced emission and mechanochromic characteristics

A novel luminogen, CZ2TPAN, with typical D-A architecture was obtained. It shows intramolecular charge transfer and aggregation-induced emission characteristics with high solid-state efficiency of 65.3%. Moreover, it exhibits reversible mechanochromic behavior between crystalline and amorphous states with remarkable emission color change from green (504 nm) to yellow (545nm).     

螺旋藻藻蓝蛋白和藻多糖对人体外周血淋巴细胞功能的影响

从螺旋藻中提取藻蓝蛋白（ＳＰＣ）和多糖（ＳＰＳ）,研究其对人体外周血淋巴细胞功能的影响。实验结果表明,ＳＰＣ和ＳＰＳ能够促进ＰＨＡ刺激淋巴细胞转化的作用,其中ＳＰＳ的促进作用有剂量依存关系。ＳＰＣ和ＳＰＳ能恢复Ｔ细胞受环磷酰胺损伤后Ｅ玫瑰花环形成能力,特别是对活性Ｅ花环（Ｅａ）的形成能力有较好的恢复作用。     

广西科学院案例研究初报

中国地方综合科研机构的案例研究,是国家自然科学基金委员会下达的中国地方综合科研机构发展研究的子课题。广西科学院案例研究是为这一子课题研究提供的一个案例。本案例包括两方面:一是广西科学院案例研究报告;一是中国地方综合科研机构调查表广西科学院部分,两者相辅相成、全面完整地显示广西科学院全貌。