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141.
Owing to the strong affinity of thiols to Au and Ag, they are often employed to modify the surfaces of nanoparticles (NPs). Recently, these strong ligand-interface interactions have been employed to control NP growth, and this technique has emerged as a unique modulation strategy for creating unconventional plasmonic hybrid nanostructures. In these systems, the roles of the non-mercapto components of the thiol molecules and their structures are still unknown. Therefore, we herein present our investigation into this phenomenon. Primary amino (–NH2) groups in thiols are found to play a key role in regulating growth kinetics, i.e., in accelerating Ag deposition on Au NPs. The–NH2 groups are thought to bring Ag ions to the particle surface by coordinating to them, and thereby assist their reduction. The effect of molecular structure is non-trivial and thus provides the possibility of selective thiol detection. Based on the dependence of kinetic modulation on the non-mercapto components and molecular structures of molecules, we demonstrate the highly sensitive and specific detection of cysteine (limit of detection: 6 nM) in a mixture of 19 natural amino acids based on Ag growth on Au nanospheres. In addition, based on this modulation effect, we reveal the entrapping of chiral thiols within the growth layer through their plasmonic circular dichroism (PCD) responses. We believe that thiol-based growth regulation has great potential for creating plasmonic nanostructures with novel functionalities. 相似文献
142.
Zihe Li Xiangming Feng Liwei Mi Jinyun Zheng Xiaoyang Chen Weihua Chen 《Nano Research》2018,11(8):4038-4048
Spinel LiMn2O4 is a widely utilized cathode material for Li-ion batteries. However, its applications are limited by its poor energy density and power density. Herein, a novel hierarchical porous onion-like LiMn2O4(LMO) was prepared to shorten the Li+ diffusion pathway with the presence of uniform pores and nanosized primary particles. The growth mechanism of the porous onion-like LiMn2O4 was analyzed to control the morphology and the crystal structure so that it forms a polyhedral crystal structure with reduced Mn dissolution. In addition, graphene was added to the cathode (LiMn2O4/graphene) to enhance the electronic conductivity. The synthesized LiMn2O4/graphene exhibited an ultrahigh-rate performance of 110.4 mAh·g–1 at 50 C and an outstanding energy density at a high power density, maintaining 379.4 Wh·kg–1 at 25,293 W·kg–1. Besides, it shows durable stability, with only 0.02% decrease in the capacity per cycle at 10 C. Furthermore, the (LiMn2O4/graphene)/graphite full-cell exhibited a high discharge capacity. This work provides a promising method for the preparation of outstanding, integrated cathodes for potential applications in lithium ion batteries. 相似文献
143.
Ribonucleic acids (RNAs) possess great therapeutic potential and can be used to treat a variety of diseases. The unique biophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stability, and potential immunogenicity, require chemical modification and development of carriers to enable intracellular delivery of RNAs for clinical use. A variety of nanomaterials have been developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat (CRISPR)/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describes the efforts to design nanomaterials that can be used for a variety of clinical indications. 相似文献
144.
Qingqing Xiong Gha Young Lee Jianxun Ding Wenliang Li Jinjun Shi 《Nano Research》2018,11(10):5281-5309
As an attractive alternative to plasmid DNA, messenger RNA (mRNA) has recently emerged as a promising class of nucleic acid therapeutics for biomedical applications. Advances in addressing the inherent shortcomings of mRNA and in the development of nanoparticle-based delivery systems have prompted the development and clinical translation of mRNA-based medicines. In this review, we discuss the chemical modification strategies of mRNA to improve its stability, minimize immune responses, and enhance translational efficacy. We also highlight recent progress in nanoparticle-based mRNA delivery. Considerable attention is given to the increasingly widespread applications of mRNA nanomedicine in the biomedical fields of vaccination, protein-replacement therapy, gene editing, and cellular reprogramming and engineering. 相似文献
145.
Atanas Radenski 《Software - Concepts & Tools》1998,19(3):122-129
This paper proposes a code reuse mechanism called module embedding that enables the building of new modules from existing ones through inheritance, overriding of procedures, and overriding of types; the paper also describes an implementation scheme for this mechanism. Module embedding is beneficial when modules and classes are used in combination and need to be extended together, or when modules are a more appropriate medium than classes. 相似文献
146.
Damping characteristics of a musical bell plays an important role in characterizing the musical sound. The total damping consists
of acoustical damping and internal damping. Acoustical damping depends upon resonating frequencies and vibration patterns
while internal damping is a material property. The acoustical damping of a vibrating structure is formulated via boundary
element method and finite element method using eigenmode decomposition. The design sensitivity of acoustical damping is derived
using an adjoint variable method of the eigenvalue problem. Design optimization of a musical bell is then performed in terms
of acoustical parameters. The goal of the optimization problem is to design a harmonically tuned bell with given acoustical
damping values. The proposed automated design process integrates finite element analysis, boundary element analysis, design
sensitivity analysis, mode-tracking algorithm and optimization module, seamlessly. It is demonstrated by numerical examples
to show practical applications. 相似文献
147.
Chun-Xia Dou Zhi-Sheng Duan Xing-Bei Jia Pei-Feng Niu 《International Journal of Control, Automation and Systems》2011,9(3):478-488
This study introduces delay independent decentralized guaranteed cost control design method based on two controller structures
for nonlinear uncertain interconnected large scale systems with time delays. First, a set of equivalent Takagi-Sugeno (T-S)
fuzzy models are extended to represent the systems. Then a decentralized state-feedback guaranteed cost performance controller
is proposed for the fuzzy systems. Based on delay independent Lyapunov functional approach, some sufficient conditions for
the existence of the controller can be cast into the feasible problem of LMIs irrespective of the sizes of the time delays
so that the system can be asymptotically stabilized for all considered uncertainties whose sizes are not larger than their
bounds. Finally, the minimizing approach is proposed to search the suboptimal upper bound value of guaranteed cost function.
Moreover, the corresponding conditions are extended into the generalized dynamic output-feedback close-loop system. Finally,
the better control performances of the proposed methods are shown by the simulation examples. 相似文献
148.
A study of a new data association and track initiation method with normalized distance squared ordering 总被引:1,自引:0,他引:1
Seung-Woo Kim Young-Taek Lim Taek-Lyul Song 《International Journal of Control, Automation and Systems》2011,9(5):815-822
In an underwater environment, measurements regarding true targets and false targets (clutter) can be made. Therefore, a suitable
data association method to exactly detect and track a target and an efficient track initiation method for judging tracks formed
by the target should be selected in this environment. This paper attempts to propose a new data association method and track
initiation method to detect and track targets more effectively. Also, the performance of the new method is tested in a series
of Monte Carlo simulation runs and is compared with the existing data association and track initiation methods in a cluttered
environment. 相似文献
149.
Airong Wei Yuzhen Wang 《International Journal of Control, Automation and Systems》2011,9(6):1067-1073
This paper deals with the problem of adaptive control of uncertain nonlinear port-controlled Hamiltonian systems subject to
actuator saturation, and proposes a number of results on the control design. Firstly, the adaptive stabilization problem is
studied, and a control design method is developed by using both the dissipative Hamiltonian structural and saturated actuator
properties. Secondly, for the case that there are both parametric uncertainties and external disturbances in the AS systems,
an adaptive H
∞ control design approach is presented. Finally, study of an example of power systems with simulations shows that the adaptive
controller proposed in this paper is effective. 相似文献
150.
Antonio J. Jara Miguel A. Zamora Antonio F. G. Skarmeta 《Personal and Ubiquitous Computing》2011,15(4):431-440
Diabetes therapy management in AAL environments, such as old people and diabetes patients homes, is a very difficult task
since many factors affect a patient’s blood sugar levels. Factors such as illness, treatments, physical and psychological
stress, physical activity, drugs, intravenous fluids and change in the meal plan cause unpredictable and potentially dangerous
fluctuations in blood sugar levels. Right now, operations related to dosage are based on insulin infusion protocol boards,
which are provided by physicians to the patients. These boards are not considering very influential factors such as glycemic
index from the diet, consequently patients need to estimate the dosage leading to dose error, which culminates in hyperglycemia
and hypoglycemia episode. Therefore, right insulin infusion calculation needs to be supported by the next generation of personal-care
devices. For this reason, a personal device has been developed to assist and consider more factors in the insulin therapy
dosage calculation. The proposed solution is based on Internet of things in order to, on the one hand, support a patient’s
profile management architecture based on personal RFID cards and, on the other hand, provide global connectivity between the
developed patient’s personal device based on 6LoWPAN, nurses/physicians desktop application to manage personal health cards,
glycemic index information system, and patient’s web portal. This solution has been evaluated by a multidisciplinary group
formed by patients, physicians, and nurses. 相似文献