scholarly journals True 3D Nanometrology: 3D-Probing with a Cantilever-Based Sensor

Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 314
Author(s):  
Jan Thiesler ◽  
Thomas Ahbe ◽  
Rainer Tutsch ◽  
Gaoliang Dai

State of the art three-dimensional atomic force microscopes (3D-AFM) cannot measure three spatial dimensions separately from each other. A 3D-AFM-head with true 3D-probing capabilities is presented in this paper. It detects the so-called 3D-Nanoprobes CD-tip displacement with a differential interferometer and an optical lever. The 3D-Nanoprobe was specifically developed for tactile 3D-probing and is applied for critical dimension (CD) measurements. A calibrated 3D-Nanoprobe shows a selectivity ratio of 50:1 on average for each of the spatial directions x, y, and z. Typical stiffness values are kx = 1.722 ± 0.083 N/m, ky = 1.511 ± 0.034 N/m, and kz = 1.64 ± 0.16 N/m resulting in a quasi-isotropic ratio of the stiffness of 1.1:0.9:1.0 in x:y:z, respectively. The probing repeatability of the developed true 3D-AFM shows a standard deviation of 0.18 nm, 0.31 nm, and 0.83 nm for x, y, and z, respectively. Two CD-line samples type IVPS100-PTB, which were perpendicularly mounted to each other, were used to test the performance of the developed true 3D-AFM: repeatability, long-term stability, pitch, and line edge roughness and linewidth roughness (LER/LWR), showing promising results.

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 451
Author(s):  
Marta Kubiak ◽  
Janine Mayer ◽  
Ingo Kampen ◽  
Carsten Schilde ◽  
Rebekka Biedendieck

In biocatalytic processes, the use of free enzymes is often limited due to the lack of long-term stability and reusability. To counteract this, enzymes can be crystallized and then immobilized, generating cross-linked enzyme crystals (CLECs). As mechanical stability and activity of CLECs are crucial, different penicillin G acylases (PGAs) from Gram-positive organisms have proven to be promising candidates for industrial production of new semisynthetic antibiotics, which can be crystallized and cross-linked to characterize the resulting CLECs regarding their mechanical and catalytic properties. The greatest hardness and Young’s modulus determined by indentation with an atomic force microscope were observed for CLECs of Bacillus species FJAT-PGA CLECs (26 MPa/1450 MPa), followed by BmPGA (Priestia megaterium PGA, 23 MPa/1170 MPa) and BtPGA CLECs (Bacillus thermotolerans PGA, 11 MPa/614 MPa). In addition, FJAT- and BtPGA CLECs showed up to 20-fold higher volumetric activities compared to BmPGA CLECs. Correlation to structural characteristics indicated that a high solvent content and low number of cross-linking residues might lead to reduced stability. Furthermore, activity seems to be restricted by small water channels due to severe diffusion limitations. To the best of our knowledge, we show for the first time in this study that the entire process chain for the characterization of diverse industrially relevant enzymes can be performed at the microliter scale to discover the most important relationships and limitations.


2020 ◽  
Author(s):  
Haozhen Dou ◽  
Mi Xu ◽  
Baoyu Wang ◽  
Zhen Zhang ◽  
Guobin Wen ◽  
...  

Abstract Cellular membranes provide ideal archetypes for molecule or ion separations with sub-angstrom scale precision, which are featured with both extremely high permeability and selectivity due to the well-defined membrane protein channels. However, the development of bioinspired membranes with artificial channels for sub-angstrom scale ethylene/ethane (0.416 nm / 0.443 nm) separation remains an uncharted territory and a significant challenge. Herein, a bioinspired nano-ordered liquid membrane is constructed by a facile ion/molecule self-assembly strategy for highly efficient ethylene/ethane separation, which mimics the structure of cellular membrane elegantly and possesses plenty of three-dimensional (3D) nanochannels. The elaborate regulation of non-covalent interactions by optimizing the ion/molecule compositions within membrane confers the nano-ordered liquid structure with interpenetrating and bi-continuous apolar domains and polar domains, which results in the formation of regular carrier wires and enormous 3D interconnected ethylene transport nanochannels. By virtue of these 3D nanochannels, the bioinspired nano-ordered liquid membrane manifests simultaneously super-high selectivity, excellent permeance and long-term stability, which exceeds previously reported ethylene/ethane separation membranes. This methodology in this work for construction of bioinspired membrane with tunable 3D nanochannels through ion/molecule self-assembly will enlighten the design and development of high-performance separation membranes for angstrom/sub-angstrom scale ion or molecule separations.


2014 ◽  
Vol 16 (36) ◽  
pp. 19307-19313 ◽  
Author(s):  
Qing Chen ◽  
Yue Hu ◽  
Chuangang Hu ◽  
Huhu Cheng ◽  
Zhipan Zhang ◽  
...  

Graphene quantum dots boost the capacitance of the graphene supercapacitor by more than 90% and with an excellent long-term stability.


2018 ◽  
Vol 89 (3) ◽  
pp. 505-517. ◽  
Author(s):  
Tung Nguyen ◽  
Eui Seon Baek ◽  
Soonshin Hwang ◽  
Kyung-Ho Kim ◽  
Chooryung J. Chung

ABSTRACT This report illustrates the successful nonsurgical and nonprosthetic camouflage treatment of a skeletal Class II open bite malocclusion combined with missing mandibular first molars bilaterally. In the mandible, the second and third molars were uprighted and protracted, substituting for the missing first molars. In the maxilla, anterior bodily retraction and full-arch intrusion were achieved following premolar and second molar extraction, which also induced autorotation of the mandible. The treatment outcome and prognosis were confirmed with three-dimensional superimposition techniques, along with long-term stability.


2020 ◽  
Vol 4 (1) ◽  
pp. 337-346 ◽  
Author(s):  
Hailiang Chu ◽  
Ying Zhu ◽  
Tingting Fang ◽  
Junqiang Hua ◽  
Shujun Qiu ◽  
...  

CoNi LDH-6 with a nano-petal structure was prepared, which exhibited excellent rate performance and long-term stability as a supercapacitor electrode.


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