Wind Farm Coordinated Control for Power Optimization

以降低风电场尾流损失、优化风场出力为目标,设计基于Laguerre函数非线性预测控制（nonlinear modelpredictive control,NLMPC）方案的风场集群控制器。该控制器应用风场动态尾流模型,通过NLMPC统一调整风场内各机组转速以提升风场功率。在控制器设计中,使用有效风速预测误差校正对预测模型失配及超短期风速预测误差进行补偿,引入Laguerre函数降低滚动时域优化计算负担并分析了控制器对风速预测误差的鲁棒性能。仿真研究表明,集群控制器能够在不同风速条件下提升风场功率、降低优化计算负担,且对风速预测模型失配与风场自然风速预测误差具有鲁棒性。

Multifunctional binder designs for lithium-sulfur batteries

Lithium-sulfur(Li-S)batteries are promising next-generation high energy density batteries but their practical application is hindered by several key problems,such as the intermediate polysulfide shuttling and the electrode degradation caused by the sulfur volume changes.Binder acts as one of the most essential components to build the electrodes of Li-S batteries,playing vital roles in improving the performance and maintaining the integrity of the cathode structure during cycling,especially those with high sulfur loadings.To date,tremendous efforts have been devoted to improving the properties of binders,in terms of the viscosity,elasticity,stability,toughness and conductivity,by optimizing the composition and structure of polymer binders.Moreover,the binder modification endows them strong polysulfide trapping ability to suppress the shuttling and decreases the swelling to maintain the porous structure of cathode.In this review,we summarize the recent progress on the binders for Li-S batteries and discuss the various routes,including the binder combination use,functionalization,in-situ polymerization and ion cross-linking,etc.,to enhance their performance in stabilizing the cathode,building the high sulfur loading electrode and improving the cyclic stability.At last,the design principles and the problems in further applications are also highlighted.

Hollow carbon microbox from acetylacetone as anode material for sodium-ion batteries

Carbon-based materials have attracted much interest as one of the promising anodes for sodium-ion batteries. However, low utilization of electrolyte and slow ion-transfer rate during electrochemical process hinder the further application of traditional bulk carbon. In order to enhance the diffusion kinetics and maintain the reversibility, hierarchical hollow carbon microbox was successfully prepared through a tunable bottom-up self-template routine for sodium-ion batteries. During annealing process, the morphology construction and activation happened synchronously. Based on that, a range of cross-linked porous nanosheet and hollow microbox were attained by manipulating reactant condition. The generation of texture and physical property are analyzed and are established linkages related to the electrochemical behavior. As results depicted in kinetic exploration and simulation based on cyclic voltammetry, the surfacecontrolled electrochemical behavior gradually turns to be the diffusion-controlled behavior as the hollow microbox evolves to porous nanosheet. The probable reason is that the rational microstructure/texture design leads to the accelerated diffusion kinetic procedure and the reduced concentration difference polarization. Sodium storage mechanism was deduced as reversible binding of Na-ions with local defects,including vacancies on sp2 graphitic layers, at the edges of flakes and other structural defects instead of intercalation. Bestowed by the morphology design, the broad pore width distribution, abundant defects/active sites and surface functionality, hollow microbox electrode delivers great electrochemical performances. This work is expected to propose a novel and effective strategy to prepare tunable hierarchical hollow carbon microbox and induce the fast kinetic of carbon anode material.

A Paleoproterozoic(Orosirian) Ophiolitic Mélange, North Yangzte Craton

Ophiolites represent fragments of ancient oceanic lithosphere,tectonically incorporated into continental margins during plate subduction or remained in the subduction–collisional orogenic belt.They provide

Diffusion Coefficients of L-Arginine in Non-Newtonian Fluid

L 精氨酸是氨基酸注射的一个重要部件。它在身体液体和血的散开具有关键重要性理解药散开和药版本。作为对学习的一个基本要求并且是为申请的一本更加珍贵的参考书在这研究，在水的答案用作类似于血的非牛顿的液体和身体液体的 polyacrylamide (PAM ) 的 L 精氨酸的散开系数用 holographic 干涉仪被测量。在散开上的分子和答案集中之中的相互作用的效果分别地被分析并且讨论。基于可伸缩阻塞的模型，一个新奇修改模型为在非牛顿的液体预言溶质的扩散性被介绍。好同意在计算价值和试验性的数据之间被完成。

Phase-field simulation of dendritic sidebranching induced by thermal noise

The influence of undercooling and noise magnitude on dendritic sidebranching during crystal growth was investigated by simulation of a phase-field model which incorporates thermal noise. It is shown that, the sidebranching is not influenced with inclusion of the nonconserved noise, therefore, in order to save the computational costs it is often neglected; while conserved noise drives the morphological instability and is dominant origin of sidebranching. The dependence of temperature field on magnitude of thermal noise is apparent, when F_u gets an appropriate value, noise can induce sidebranching but not influence the dendritic tip operating state. In the small undercooled melt, the thermal diffusion layer collected around the dendrite is thick, which suppresses the growth of its sidebranching and makes the dendrite take on the morphology of no sidebranching, but when the undercooling is great, the thermal diffusion layer is thin, which is advantageous to the growth of the sidebranching and the dendrite presents the morphology of the developed sidebranching.

DnaQ mediates directional spacer acquisition in the CRISPR-Cas system by a time-dependent mechanism

In the spacer acquisition stage of CRISPR-Cas immunity,spacer orientation and protospacer adjacent motif(PAM)removal are two prerequisites for functional spacer integration.Cas4 has been implicated in both processing the prespacer and determining the spacer orientation.In Cas4-lacking systems,host 3′–5′DnaQ family exonucleases were recently reported to play a Cas4-like role.However,the molecular details of DnaQ functions remain elusive.Here,we characterized the spacer acquisition of the adaptation module of the Streptococcus thermophilus type I-E system,in which a DnaQ domain naturally fuses with Cas2.We presented X-ray crystal structures and cryo-electron microscopy structures of this adaptation module.Our biochemical data showed that DnaQ trimmed PAM-containing and PAM-deficient overhangs with different efficiencies.Based on these results,we proposed a time-dependent model for DnaQ-mediated spacer acquisition to elucidate PAM removal and spacer orientation determination in Cas4-lacking CRISPR-Cas systems.

Seismic damage-cracking analysis of arch dams using different earthquake input mechanisms

In this study, a nonlinear model is presented for analysis of damage-cracking behavior in arch dams during strong earthquakes using different seismic input mechanisms. The nonlinear system includes a plastic-damage model for cyclic loading of concrete considering strain softening and a contact boundary model of contraction joint opening. Two different earthquake input mechanisms are used for comparison, including massless foundation input model and viscous-spring boundary model considering radiation damping due to infinite canyon. The results demonstrate that effects of seismic input mechanism and radiation damping on nonlinear response and damage-cracking of the dam are significant. Compared with the results of using massless foundation input model, the damage-cracking region and contraction joint opening are substantially reduced when using viscous-spring boundary model to take into account radiation damping. However, if the damping ratio of the dam is artificially increased to about 10%―15% for massless foundation input model, the joint opening and damage-cracking of the dam are comparable to the results obtained from the viscous-spring boundary model.

Current trauma care system and trauma care training in China

损伤是威胁生活的现代疾病。结果能被成本效率、迅速的损伤照顾仅仅优化，它除了损伤照顾系统的造成分裂的革新开始必要能力和概念的革命的改进。根据来自发达国家的经验，系统的损伤照顾训练在损伤照顾上是归纳和改进的奠基石，例如进展损伤生活支持(ATLS ) 。当前，医院前紧急情况医疗服务(他们) 是在中国的健康服务的基础结构的必要元素之一，它对损伤照顾系统也基本。在此，有独立知识产权权利的训练的中国损伤照顾(CTCT ) 被开始了并且由中国损伤外科医生协会发射了也在损伤照顾的地里扩大新概念和技术在惯例增强通常接受得好的标准化协议。这篇文章考察损伤照顾系统以及训练的损伤照顾的当前的地位。

A vicinal effect for promoting catalysis of Pd1/TiO2:supports of atomically dispersed catalysts play more roles than simply serving as ligands

Atomically dispersing metal atoms on supports has been emerging as an effective strategy to maximize the atom utilization of metals for catalysis. However, due to the lack of effective tools to characterize the detailed structure of metal-support interface, the chemical functions of supports in atomically dispersed metal catalysts are hardly elucidated at the molecular level. In this work, an atomically dispersed Pd_1/TiO_2 catalyst with Ti(Ⅲ) vicinal to Pd is prepared and used to demonstrate the direct involvement of metal atoms on support in the catalysis of dispersed metal atoms. Systematic studies reveal that the Ti(Ⅲ)-O-Pd interface facilitates the activation of O_2 into superoxide(O_2^-), thus promoting the catalytic oxidation. The catalyst exhibits the highest CO turn-over frequency among ever-reported Pd-based catalysts,and enhanced catalysis in the combustion of harmful volatile organic compound(i.e., toluene) and greenhouse gas(i.e., methane). The demonstrated direct involvement of metal atoms on oxide support suggests that the real active sites of atomically dispersed metal catalysts can be far beyond isolated metal atoms themselves. Metal atoms on oxide supports in the vicinity serve as another vector to promote the catalysis of atomically dispersed metal catalysts.

基于绝对丰度的植物根际微生物群落“扩增-选择”组装模型

在自然界中,植物根系与大量的微生物互作.基于传统的微生物相对丰度数据,研究人员提出了根际微生物群落的多步筛选组装模型.该模型认为:微生物依次在根外土、根际土和根内逐步被筛选,形成根际特异的微生物群落.通过分别定量蒺藜苜蓿和水稻的根外土、根际土及根内微生物群落的绝对丰度发现:与根外土相比,主要菌门在根际土中的绝对丰度都显著扩增,其扩增幅度为2~30倍不等.不同微生物扩增倍数可能由微生物自身扩增速率、微生物与微生物互作、植物与微生物互作等因素决定.经根际土扩增的微生物进一步被根筛选,形成特异的微生物群落.基于微生物绝对丰度,提出了根际微生物群落组装的"扩增-选择"新模型.该模型将有助于深入认识和利用植物微生物群落提高植物的环境适应性.

Nonlinear quantum interferometry with Bose condensed atoms

In quantum interferometry, it is vital to control and utilize nonlinear interactions for the achievement of high-precision measurements. Due to their long coherence time and high controllability, ultracold atoms including Bose condensed atoms have been widely used for quantum interferometry. Here, we review recent progress in theoretical studies of quantum interferometry with Bose condensed atoms. In particular, we focus on nonlinear phenomena induced by atom-atom interactions, and how to control and utilize these nonlinear phenomena. With a mean-field description, due to atom-atom interactions, matter-wave solitons appear in the interference patterns, and macroscopic quantum self-trapping exists in Bose-Josephson junctions. With a many-body description, atom-atom in- teractions can generate non-classical entanglement, which can be utilized to achieve high-precision measurements beyond the standard quantum limit.

有机太阳电池新时代:聚合物受体

Organic solar cells(OSCs)have made fast advance with prominent power conversion efficiencies(PCEs)achieved in non-fullerene OSCs in recent years[1].Among various types of OSCs,allpolymer solar cells(APSCs)consisting of a polymer donor and a polymer acceptor are promising power sources for portable and wearable electronics due to their intrinsic advantages in device stability and mechanical flexibility[2].

Progress in the beam commissioning of separated function RFQ accelerator

Separated Function RFQ (SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low frequency. It introduces gap accelerating in the quadrupole electrodes, and therefore it has higher accelerating efficiency than the conventional RFQ accelerator. The first SFRFQ prototype cavity has been specially designed and constructed as a post accelerator to accelerate O+ beam from 1.03 MeV to 1.64 MeV. Based on accomplishment of low power measurement and high power test, the beam commissioning was carried out to verify its feasibility. The measured energy gain per cell of SFRFQ is 45 keV, which is about 60% higher than that of Peking University Integral Split Ring (ISR) RFQ.

Improved Mesenchymal Stem Cell Survival in Ischemic Heart through Electroacupuncture＊

Objective： To investigate whether electroacupuncture （EA） can promote cell survival and enhance heart function of mesenchymal stem cells （MSCs） therapy. Methods： MSCs were isolated from bone marrow and expanded in Minimum Essential Medium Alpha （α-MEM）. MI was induced in 72 Sprague-Dawley （S-D） rats by ligation of the left anterior descending coronary artery （LAD） for 30 min and reperfusion. MI rats randomly received injection of 1 x 106 Dil-labeled MSCs alone （n=24, MSC group）, or plus electroacupuncture （EA） at Neiguan （PC6, n=24, EA＋MSC group）, or saline （n=24, saline group）. EA treatment was performed for 4 days. Another 24 rats were subjected to chest-open surgery without LAD occlusion and treatment （sham group）. Three time points, 4, 14 and 28 days （n=8 for each group） were included in this study. The survival of transplanted MSCs and the protective gene expression were analyzed by reverse transcriptase polymerase chain reaction （RT-PCR） and Western blot at day 4 and 14. Left ventricular remodeling, cardiac function, infarction area, fibrosis and capillary density were analyzed at day 28. Results： EA can enhance MSC survival （2.6-fold up） at day 4. Big capillary density was 53% higher in EA＋MSC treated group than MSC alone group. Furthermore, the rats treated by EA reduced the fibrosis and had 36% smaller infarct size comparing to MSC alone. EA also attenuated left ventricular remodeling and enhanced the functional recovery of infarcted hearts at week 4. Conclmion： EA at Neiguan acupoint can promote the stem cell survival and improve ischemic heart function. EA could become a useful approach in stem cell therapy for ischemia heart diseases.

Simulation of fine polydisperse particle condensational growth under an octadecane-nitrogen atmosphere

The evolution of particle size distribution （PSD） of fine polydisperse particles at high number concen- trations （7105 cm-3） was simulated through a combined model employing direct quadrature method of moments （DQMOM） with heat and mass transfer equations. The PSD was assumed to retain log-normal distribution during the heterogeneous condensation process. The model was first verified by exact solu- tion and experimental data prior to investigating the influence of initial conditions on final PSD under an octadecane-nitrogen atmosphere. Low particle number concentrations and high vapor concentrations were beneficial to shift the PSD to larger particles having a narrower distribution. Additionally, vapor depletion has more influence on the final PSD than the heat release parameter for a number concentra- tion of 10^6 cm^-3. This study may assist the design process of a gas-solid separating cyclone, to eliminate dust from high-temperature volatiles by pyrolysis of solid fuels.

The circadian clock ticks in plant stress responses

The circadian clock,a time-keeping mechanism,drives nearly 24-h self-sustaining rhythms at the physiological,cellular,and molecular levels,keeping them synchronized with the cyclic changes of environmental signals.The plant clock is sensitive to external and internal stress signals that act as timing cues to influence the circadian rhythms through input pathways of the circadian clock system.In order to cope with environmental stresses,many core oscillators are involved in defense while maintaining daily growth in various ways.Recent studies have shown that a hierarchical multi-oscillator network orchestrates the defense through rhythmic accumulation of gene transcripts,alternative splicing of mRNA precursors,modification and turnover of proteins,subcellular localization,stimuli-induced phase separation,and long-distance transport of proteins.This review summarizes the essential role of circadian core oscillators in response to stresses in Arabidopsis thaliana and crops,including daily and seasonal abiotic stresses(low or high temperature,drought,high salinity,and nutrition deficiency)and biotic stresses(pathogens and herbivorous insects).By integrating time-keeping mechanisms,circadian rhythms and stress resistance,we provide a temporal perspective for scientists to better understand plant environmental adaptation and breed high-quality crop germplasm for agricultural production.

The design, synthesis, conformation and bioactivity of deltorphins analogues

Deltorphins are endogenous linear heptapeptides, isolated from skin extracts of frogs(genus phyllomedusa) in 1989, which have a higher affinity and selectivity for δopioidbinding sites than any other known natural compound. The analgesic activity,

Deciphering the impact of PEG antifouling layer on surface attached functional peptides in regulating cell behaviors

It is highly desired to have bioactive surfaces for biomaterials and controllable interactions with cells.These functions were widely achieved by attaching functional peptides to the surface of biomaterials.It is well known that an antifouling layer can help reducing the nonspecific cell attachment.However,it is unclear how an antifouling PEG layer affects the function of peptides attached on material surface in controlling cell behavior.This highlight introduced the recent JACS paper from Prof.Liu and coworkers in addressing this question thoroughly.