Preparation of “pomegranate”-like QD/SiO2/poly(St-co-MAA) fluorescent nanobeads with two steps to improve stability and biocompatibility

2021 ◽  
Author(s):  
Qianrui Xu ◽  
Yang Wang ◽  
Pencheng Gao ◽  
Yong Jiang
Keyword(s):  
Quantitative Measurement ◽  
The Stability ◽  
Improve Stability ◽  
Target Analyte

Fluorescent nanobeads are widely used because of their advantages of visualization, sensitivity and quantitative measurement of target analyte. In terms of these applications, the stability and biocompatibility of fluorescent nanobeads...

Optimization of Journal Bearing Profile for Higher Dynamic Stability Limits

2012 ◽  
Vol 135 (1) ◽  
Author(s):  
Rodrigo Nicoletti
Keyword(s):  
Journal Bearing ◽  
Optimization Procedure ◽  
Control Points ◽  
Time Domain Simulation ◽  
Rotating System ◽  
Stability Margins ◽  
Dynamic Coefficients ◽  
The Stability ◽  
Stability Limits ◽  
Improve Stability

This work presents an optimization procedure to find bearing profiles that improve stability margins of rotor-bearing systems. The profile is defined by control points and cubic splines. Stability margins are estimated using bearing dynamic coefficients, and obtained solutions are analyzed as a function of the number of control points and of the Sommerfeld number at optimization. Results show the feasibility of finding shapes for the bearing that significantly improve the stability margins. Some of the obtained solutions overcome the stability margins of conventional bearings, such as the journal bearing and preloaded bearings with 0.5 and 0.67 preload. A time domain simulation of a flexible shaft rotating system supported by such bearings corroborates the results.

Disturbance rejection by online ZMP compensation

Robotica ◽  
2008 ◽  
Vol 26 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Vadakkepat Prahlad ◽  
Goswami Dip ◽  
Chia Meng-Hwee
Keyword(s):  
Body Weight ◽  
Disturbance Rejection ◽  
Humanoid Robot ◽  
Additional Weight ◽  
Four Corners ◽  
Compensation Technique ◽  
Novel Method ◽  
Zero Moment ◽  
The Stability ◽  
Improve Stability

SUMMARYA novel method of Zero-Moment-Point (ZMP) compensation is proposed to improve the stability of locomotion of a biped, which is subjected to disturbances. A compensating torque is injected into the ankle-joint of the foot of the robot to improve stability. The value of the compensating torque is computed from the reading of the force sensors located at the four corners of each foot. The effectiveness of the method is verified on a humanoid robot, MANUS-I. With the compensation technique, the robot successfully rejected disturbances in different forms. It carried an additional weight of 390 gm (17% of body weight) while walking. Also, it walked up a 10° slope and walked down a 3° slope.

scholarly journals ATMOSPHERIC ENVIRONMENT DETECTION METHOD BASED ON MULTI-ROTOR UAV PLATFORM

2018 ◽  
Vol XLII-3/W5 ◽  
pp. 67-71
Author(s):  
A. Shen ◽  
S. Zhou ◽  
S. Peng
Keyword(s):  
Detection Method ◽  
Center Of Gravity ◽  
Atmospheric Environment ◽  
Detection Accuracy ◽  
Flight Safety ◽  
Rotor Speed ◽  
Gradual Process ◽  
The Stability ◽  
Environment Detection ◽  
Improve Stability

<p><strong>Abstract.</strong> For the method of atmospheric detection based on multi-rotor UAV, the effects of flight safety and airflow on detection accuracy are analyzed. The detector mounted on the multi-rotor drone should be highly symmetrical and the center of gravity should be on the same vertical line as the center of gravity of the drone. Mounting the detector above the drone's fuselage will reduce the stability of the drone, and lowering it will improve stability, but for models with high stability, placing it below will affect the maneuverability of the drone. The airflow interference in the area where the detector can be placed near the fuselage is related to the drone: the faster the rotor speed, and the closer the rotor is to the fuselage, the stronger the airflow interference. At the same time, the influence of airflow disturbance on temperature and humidity has a gradual process. Waiting for a period of time after starting the drone can change the error into a fixed error for post-processing. This method was used to detect a pollution process and achieved good results.</p>

New approaches for biomarker stability determination in regulated bioanalysis: trending, bridging and incurred samples

Bioanalysis ◽  
2019 ◽  
Vol 11 (20) ◽  
pp. 1837-1844 ◽  
Author(s):  
Sumit Kar ◽  
Clarinda Islam
Keyword(s):  
Statistical Analysis ◽  
Protease Activity ◽  
Respiratory Diseases ◽  
Complex Matrix ◽  
New Approaches ◽  
Disease States ◽  
Analysis Methodology ◽  
Sample Stability ◽  
The Stability ◽  
Improve Stability

Aim: Determining the stability of biomarkers continues to present challenges. Disease states, complex matrices and differences between recombinant and endogenous analytes require new approaches to maintain stability and measure it. In this report, we determine stability for two assays using trending and statistical analysis. Methodology & results: Monitoring trends helps identify out of specification measurements and determine whether concerns are due to the stability of the analyte. We also describe challenges presented when measuring arginase activity in human sputum, a complex matrix, for respiratory diseases. We controlled preanalytical protease activity and collection heterogeneity and monitored incurred sample stability to improve stability of arginine. Conclusion: These new approaches to achieving and determining biomarker stability may provide solutions for increasingly complex biomarker measurements.

scholarly journals Quantitative motion detection of in-hand objects for robotic grasp manipulation

2019 ◽  
Vol 16 (3) ◽  
pp. 172988141984633
Author(s):  
Xueyong Li ◽  
Kai Zhao ◽  
Changhou Lu ◽  
Yonghui Wang
Keyword(s):  
Motion Detection ◽  
Decomposition Method ◽  
Quantitative Measurement ◽  
Singular Value ◽  
Singular Value Decomposition Method ◽  
Innovative Method ◽  
The Stability ◽  
Coordinate Changes ◽  
Value Decomposition ◽  
Robotic Grasp

In an actual grasp operation, grasp accidents (slant, rolling, turning over, and dropping) of in-hand objects occur frequently. Quantitative motion detection of in-hand objects is critical to optimize the grasp configuration and to improve the stability and dexterity of a grasp manipulation. In this article, an innovative method for quantitative measurement of the motions of in-hand objects is presented. Firstly, the slip information at object–finger interface between adjacent states is detected by three omnidirectional slip sensors; next, singular value decomposition method is applied to calculate the rotation and translation matrices according to the relative coordinate changes extracted from the slip information. Finally, Euler angles and the linear displacements which illustrate the motion of in-hand objects are quantitatively measured from the translation matrix and the rotation matrix, and the continuous motion track can be further established. Experiment results show that the proposed method is effective in detecting multiple motion information of in-hand objects.

scholarly journals Enhancing moisture tolerance in efficient hybrid 3D/2D perovskite photovoltaics

2018 ◽  
Vol 6 (5) ◽  
pp. 2122-2128 ◽  
Author(s):  
Teck Ming Koh ◽  
Vignesh Shanmugam ◽  
Xintong Guo ◽  
Swee Sien Lim ◽  
Oliver Filonik ◽  
...  
Keyword(s):  
Conversion Efficiency ◽  
High Efficiency ◽  
Trap State ◽  
Successful Strategy ◽  
2D Structure ◽  
State Densities ◽  
The Stability ◽  
Improve Stability

Hybrid 3D/2D perovskites combine the high efficiency of 3D perovskites and the stability of 2D perovskites, and possess longer photoluminescence lifetimes, lower trap-state densities and enhanced moisture tolerance. The hybrid 3D/2D structure is a successful strategy to improve stability without sacrificing conversion efficiency.

scholarly journals The control system for the magnetic suspension comparator system for vacuum-to-air mass dissemination

ACTA IMEKO ◽  
2017 ◽  
Vol 6 (2) ◽  
pp. 75 ◽  
Author(s):  
Corey Stambaugh
Keyword(s):  
Control System ◽  
High Precision ◽  
Atmospheric Pressure ◽  
Magnetic Suspension ◽  
Large Role ◽  
Air Mass ◽  
Mass Comparison ◽  
The Stability ◽  
Improve Stability

<p dir="LTR" align="JUSTIFY">High precision mass comparisons are typically performed such that both masses are measured under nearly identical conditions. However, there are situations where an artefact needs to be calibrated against a standard kept under different conditions. For example, the new realization of the kilogram will be carried out in vacuum but the majority of calibrations services are performed at atmospheric pressure. At the National Institute of Standards and Technology we have developed an apparatus to perform direct mass comparison under such a condition using magnetic suspension. The stability of the magnetically suspended portion of the system plays a large role in the overall uncertainty of a measurement. Here, the control system for the magnetic suspension and the improvements that have been made to improve stability are described.</p>

scholarly journals Estimation of the stability of a fishing vessel during purse seining

2021 ◽  
Vol 937 (3) ◽  
pp. 032057
Author(s):  
A V Ivanovskaya ◽  
E V Bogatyreva
Keyword(s):  
Three Dimensional ◽  
Static Stability ◽  
Tension Force ◽  
Geometrical Parameters ◽  
Dimensional Representation ◽  
Fishing Vessel ◽  
Three Dimensional Representation ◽  
The Stability ◽  
Improve Stability ◽  
Purse Seining

Abstract One of the reasons for the emergency of a fishing vessel, as well as for the failure of fishing equipment, is the sudden tension of the purse rope, which occurs when the fishing equipment is pulled. As a result of the loss of stability the vessel may enter the encircled seine area and even capsize. There are a number of measures to improve stability during the operation of the vessel. However, when designing fishing equipment, it is necessary to know forces acting on the vessel from the seine side. The article presents a method for assessing the static stability of a vessel with a static application of the tension force of the purse rope. As a result of the study, an expression for determining the static heel angle using a three-dimensional representation of the vessel is given. During simulation the geometrical parameters of the purse rope in the process of purse seine were taken into account. The tension force of the purse rope is also presented as a variable.

Evaluation of Static and Dynamic Stability of Spinal Cord Injuries: What Are the Gaps

2020 ◽  
Vol 22 (1) ◽  
pp. 1-5
Author(s):  
Hussein Asiabi ◽  
Mokhtar Arazpour ◽  
Mahmoud Bahramizadeh ◽  
Mohammad Taghi Karimi
Keyword(s):  
Spinal Cord ◽  
Dynamic Stability ◽  
Normal Subjects ◽  
Assistive Devices ◽  
Quiet Standing ◽  
Stability Parameters ◽  
Cord Injury ◽  
Lesion Level ◽  
The Stability ◽  
Improve Stability

Background. Depending on the level of lesion, spinal cord injury (SCI) individuals have limited ability to stand and walk. They have to use various assistive devices to restore their abilities. The aim of this study was to evaluate the stability of SCI individuals during walking and quiet standing. Material and methods. Three groups: normal subjects and SCI individuals with complete and incomplete lesions, were enrolled. Stability of the subjects was evaluated based on center of pressure (COP) sways in quiet standing and spatiotemporal gait parameters in walking. The difference between the stability of normal and SCI subjects was determined by use of the two-sample t test. The correlation between the mean values of stability parameters in standing and walking and lesion level was determined by use of Pearson’s correlation. Results. The stability of SCI subjects during quiet standing was better than that of normal subjects. How­ever, their dynamic stability was significantly less than normal subjects. The dynamic stability of complete and incomplete SCI subjects did not differ significantly (P-value<0.05). There was no correlation between lesion level and stability parameters. Conclusion. 1. SCI individuals suffer mostly from lack of dynamic stability, which does not depend on their lesion levels. 2. It seems that this problem may be due to rehabilitation methods used to improve stability in these patients. 3. It is recommended that new methods of rehabilitation or assistive devices should be used to improve stability of these individuals.

Lycopene Nanoparticles Coated with Microemulsions to Improve Stability

2015 ◽  
Vol 1120-1121 ◽  
pp. 897-902 ◽  
Author(s):  
Zhu Fen Lu ◽  
Yan Zhong Chen ◽  
Jun Feng Ban ◽  
Guang Han Deng ◽  
Huang Xin ◽  
...  
Keyword(s):  
High Pressure ◽  
Zeta Potential ◽  
Drug Loading ◽  
Drug Efficacy ◽  
Tween 20 ◽  
Microemulsion System ◽  
Loading Capacity ◽  
High Pressure Homogenization ◽  
The Stability ◽  
Improve Stability

Delivery systems play important roles in improving drug efficacy. In particular, insoluble functional pigments must be handled carefully when increasing their solubility, in order to ensure that they remain active. In this study, the nanoparticles were coated by the oil phase in the microemulsion system (NPs-SEs), and this system was found to both increase the stability of the drug and improve drug loading. NPs-SEs containing lycopene, soybean oil, Span-40, Tween-20, stabilizer and glycerol were prepared by high pressure homogenization technology. It was characterized and its droplet size, and Zeta potential were 181±15 nm ( PDI 0.092±0.01), -70.83±1.64mV, respectively. The drug loading capacity of NPs-SEs was 1.02±0.16mg/ml and was nearly 4 times more than the highest concentration of lycopene O/W emulsion.

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