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1.
NBI fast ion losses in the presence of the toroidal field ripple on EAST have been investigated by using the orbit code GYCAVA and the NBI code TGCO. The ripple effect was included in the upgraded version of the GYCAVA code. It is found that loss regions of NBI fast ions are mainly on the low field side near the edge in the presence of ripple. For co-current NBIs, the synergy effect of ripple and Coulomb collision on fast ion losses is dominant, and fast trapped ions located on the low field side are easily lost. The ripple well loss and the ripple stochastic loss of fast ions have been identified from the heat loads of co-current NBI fast ions. The ripple stochastic loss and the collisioninduced loss are much larger than the ripple well loss. Heat loads of lost fast ions are mainly localized on the right side of the radio frequency wave antennas from the inside view toward the first wall. For counter-current NBIs, the first orbit loss due to the magnetic drift is the dominant loss channel. In addition, fast ion loss fraction with ripple and collision for each NBI linearly increases with the effective charge number, which is related to the pitch angle scattering effect.  相似文献   
2.
Protein oxidation is considered as an important issue in food preservation process. In the present study, the potential influence of protein oxidation on water holding capacity and protein structure of jumbo squid (Dosidicus gigas) mantle was investigated. After the hydroxyl radical oxidation, it was found that the carbonyl, surface hydrophobicity and dityrosine content of myofibrillar protein significantly increased (P < 0.05), while the content of total sulphydryl decreased significantly (P < 0.01). Meanwhile, the fluorescence intensity of squid was weakened, and the maximum absorption peak of fluorescence red shift as the H2O2 concentration increased. The sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed that not only the protein cross-linking but also degradation could have occurred. The content of α-helix decreased, the content of β-sheet, β-turn and the unordered structures increased after oxidation. In addition, oxidation resulted in a decrease in water holding capacity. Taken together, oxidation resulted in the damage of the myofibrillar structure, the increase in muscle loss rate and the decrease in water holding capacity.  相似文献   
3.
A sustainable power source is a key technical challenge for practical applications of electrically responsive soft robots, especially the required voltage is over several thousand volts. Here, a practicable new technology, triboelectric soft robot (TESR) system with the primary characteristics of power source from mechanical energy, is developed. At its heart is TESR with bioinspired architectures made of soft-deformable body and two triboelectric adhesion feet, which is driven and accurately controlled through triboelectric effect, while reaching maximum crawling speeds of 14.9 mm s−1 on the acrylic surface. The characteristics of the TESR, including displacement and force, are tested and simulated under the power of a rotary freestanding triboelectric nanogenerator (RF-TENG). Crawling of TESR is successfully realized on different materials surfaces and different angle slopes under the driven of RF-TENG. Furthermore, a real-time visual monitoring platform, in which TESR carries a micro camera to transmit images in a long narrow tunnel, is also achieved successfully, indicating that it can be used for fast diagnosis in an area inaccessible to human beings in the future. This study offers a new insight into the sustainable power source technologies suitable for electrically responsive soft robots and contributes to expanding the applicability of TENGs.  相似文献   
4.
针对湿式球磨机在磨矿过程中内部负荷靠专家经验难以准确预测的问题,提出一种基于改进的共生生物搜索(ameliorated symbiotic organisms search,简称ASOS)-极限学习机(extreme learning machine,简称ELM)的磨机负荷软测量方法。首先,利用ELM算法建立磨机负荷软测量模型,运用ASOS算法优化软测量模型的隐含层参数;其次,以筒体振动与振声信号的特征信息构建磨机负荷特征向量,并将其作为软测量模型的输入,将磨机负荷参数作为输出;最后,通过磨矿负荷检测实验和对比分析表明,磨机负荷软测量模型的负荷参数预测准确率较高,泛化能力较强,为磨机磨矿效率的提高及控制优化提供了有益的指导。  相似文献   
5.
Zu  Guoqing  Lu  Yukuan  Yan  Yi  Zhang  Xiaoming  Zhao  Jingwei  Du  Wei  Ran  Xu  Jiang  Zhengyi 《Metals and Materials International》2020,26(2):248-259
Metals and Materials International - The flow behaviour and microstructure characteristics of a ferritic stainless steel were investigated using plain strain compression test on a Gleeble 3500...  相似文献   
6.
Compared with inorganic or perovskite solar cells, the relatively large non-radiative recombination voltage losses (ΔVnon-rad) in organic solar cells (OSCs) limit the improvement of the open-circuit voltage (Voc). Herein, OSCs are fabricated by adopting two pairs of D–π–A polymers (PBT1-C/PBT1-C-2Cl and PBDB-T/PBDB-T-2Cl) as electron donors and a wide-bandgap molecule BTA3 as the electron acceptor. In these blends, a charge-transfer state energy (ECT) as high as 1.70–1.76 eV is achieved, leading to small energetic differences between the singlet excited states and charge-transfer states (ΔECT ≈ 0.1 eV). In addition, after introducing chlorine atoms into the π-bridge or the side chain of benzodithiophene (BDT) unit, electroluminescence external quantum efficiencies as high as 1.9 × 10−3 and 1.0 × 10−3 are realized in OSCs based on PBTI-C-2Cl and PBDB-T-2Cl, respectively. Their corresponding ΔVnon-rad are 0.16 and 0.17 V, which are lower than those of OSCs based on the analog polymers without a chlorine atom (0.21 and 0.24 V for PBT1-C and PBDB-T, respectively), resulting in high Voc of 1.3 V. The ΔVnon-rad of 0.16 V and Voc of 1.3 V achieved in PBT1-C-2Cl:BTA3 OSCs are thought to represent the best values for solution-processed OSCs reported in the literature so far.  相似文献   
7.
秸秆等生物质焚烧发电时产生的含氯气体和碱金属氯化物腐蚀使受热面金属管道的服役寿命比煤电机组显著降低。 管材表面堆焊镍基耐腐蚀合金的技术尽管可显著提高管道服役寿命,但存在工作效率低、不适合现场施工、管道热变形等诸多问题。 采用可现场施工的空气超音速火焰喷涂(HVAF)在 TP347H 耐热钢表面,制备了 Inconel 镍基耐高温腐蚀涂层,研究了 TP347H 耐热钢喷涂 Inconel 625 合金涂层前后的长期高温腐蚀特性(550 ℃ ,500 h),验证了 HVAF Inconel 625 合金涂层的高温含氯腐蚀防护作用。 显微观察结果表明,优化工艺参数条件下 HVAF 涂层组织致密、 孔隙率低至 0. 72%,与基材结合良好。 腐蚀增重结果表明,采用 HVAF 制备 Inconel 625 合金涂层后,TP347H 耐热钢的腐蚀增重降低 7. 6 倍,耐腐蚀性能显著提升。 冲蚀试验结果表明,HVAF Inconel 625 合金涂层在最初阶段由于表层凸起颗粒的剥落而冲蚀性能极低,进入稳定阶段后耐冲蚀性能提高,与 TP347H 基材的耐冲蚀性能相当。  相似文献   
8.
Cui  Xiaotao  Xiao  Jing  Cao  Yang  Zhu  Jia 《Multimedia Tools and Applications》2022,81(24):34367-34386
Multimedia Tools and Applications - Video-text cross-modal retrieval is significant to computer vision. Most of existing works focus on exploring the global similarity between modalities, but...  相似文献   
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10.
随着定位技术的快速发展,面向5G-Advanced的高精度定位技术正受到越来越多的关注。首先,介绍了第三代合作伙伴计划(3rd Generation Partnership Project,3GPP)Rel-16和Rel-17的5G定位标准现状和Rel-18的5G-Advanced定位技术增强方向。其次,重点研究了5G正交频分复用(orthogonal frequency division multiplexing,OFDM)信号模型和载波相位定位技术需要解决的3个关键算法:基于锁相环的载波相位测量算法、基于参考终端的双差分算法和基于拓展卡尔曼滤波的用户设备(user equipment,UE)位置解算算法。最后,分析了低功耗高精度定位技术方案和基于定位参考设备的定位精度增强技术方案。  相似文献   
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