China
Africa
Explore chapters and articles related to this topic
Mass-Sensitive Based Biosensors
Published in Sibel A. Ozkan, Bengi Uslu, Mustafa Kemal Sezgintürk, Biosensors, 2023
Erdoğan Ozgür, Yeşeren Saylan, Semra Akgönüllü, Adil Denizli
Mass-based biosensors are phenomenon platforms for monitoring of interactions and the analysis can be designed as label-free which means that interaction between biosensor chip metal surface and the target analyte is responded directly without application of any specific reagent or sample processing (121). Quartz is the specific material having piezoelectric features that means talent to create potency when mechanically squeezed or mechanically deformed when oriented dipole is given on crystal surface. These biosensors are deeply mass-sensitive and can monitor changes of mass at the nanogram level. QCM has appeared as the most common sensor platform in the quartz form of biosensors tools. The mass-sensitive based biosensors are highly sensitive to the mass change on the crystal biosensor surface; their detection for a target has pretty perfect excellence with designed special nanomaterials (122).
Advanced treatment technologies for removal of contaminants of emerging concern
Published in Manish Kumar, Sanjeeb Mohapatra, Kishor Acharya, Contaminants of Emerging Concerns and Reigning Removal Technologies, 2022
Om Prakash, Deepak Panchal, Abhishek Sharma, Sukdeb Pal
As of now, there is no drinking or clean water guidelines for CECs except in some of the developed countries. These guidelines are formed on the basis of existing knowledge of toxicity and acute health effects caused by CECs. Even at nanogram level, these contaminants can pose acute as well as long-term deleterious/adverse effects on living beings. These effects can be hormonal changes or disruption of metabolic pathways including inhibition of nucleic acid formation and protein synthesis. CECs’ Log Kow values are greater than 3 that can result into bioaccumulation of CECs in the organisms’ tissues (Rizzo et al., 2009). The presence of endocrine disruptors in the aquatic environment and potential adverse effects on humans and biota require a constant monitoring of their fates in wastewater. Certainly, the existing knowledge is limited, and there is an urgent need for extensive investigation before setting up guidelines for CECs in drinking water. On the other hand, elimination of these CECs is of utmost importance and necessary in order to reduce the toxicity toward public health and environment.
General Methods of Sample Preparation for Infrared Hyphenated Techniques
Published in Patricia B. Coleman, Practical Sampling Techniques for INFRARED ANALYSIS, 2020
The major growth in interest in combining gas chromatography and infrared spectrometry occurred when the high resolution GC (HRGC) associated with capillary column technology was coupled to FT-IR in the mid to late 1970s and early 1980s.27,28 Analytical performance improved and detection limits decreased below the microgram level and into the nanogram range. In addition to the much improved hardware performance, the software also developed to provide “on-the-fly” HRGC/FT-IR. This development enabled the analyst to see an infrared spectrum of the material almost immediately as each component exited the column. The experienced operator could then identify many materials by visual inspection of the component spectra as they appeared on the computer screen.
Recent advances in the synthesis of and sensing applications for metal-organic framework-molecularly imprinted polymer (MOF-MIP) composites
Published in Critical Reviews in Environmental Science and Technology, 2023
Yongbiao Hua, Deepak Kukkar, Richard J. C. Brown, Ki-Hyun Kim
QCM is a mass sensing technique that can sense nanogram levels of the target analytes by measuring variations in the oscillating frequency when target analytes are loaded onto the surface of a resonator (Malik et al., 2019). On the basis of mass change, QCM is well suited as a transducer element for the fabrication of sensors because of its rapid response, simple operation, highly stable signal, and portability (Emir Diltemiz et al., 2017). To improve selectivity toward the target species, MIPs with high intrinsic selectivity are combined with QCM techniques, which enables outstanding recognition of imprinted polymeric receptors and efficient gravimetric transduction for the trace-level, real-time detection of target analytes (Mujahid et al., 2018). Recently, a UiO-66 immobilized MIP–based QCM sensor was proposed for the specific and sensitive determination of tyramine (Yao et al., 2020). The high specific surface area of UiO-66 provided many imprinted sites for tyramine recognition with the aid of tailor-made MIPs. On the basis of the frequency response (Δƒ) of QCM against tyramine concentrations, a good linear relationship was obtained between the frequency change and tyramine concentration across a range of 583–3640 nM (Figure S4(C)). This UiO-66@MIP-based QCM sensor exhibited an LOD of 4.49 × 105 pM for sensing tyramine (Yao et al., 2020).
The National Direct-Drive Program: OMEGA to the National Ignition Facility
Published in Fusion Science and Technology, 2018
S. P. Regan, V. N. Goncharov, T. C. Sangster, E. M. Campbell, R. Betti, K. S. Anderson, T. Bernat, A. Bose, T. R. Boehly, M. J. Bonino, D. Cao, R. Chapman, T. J. B. Collins, R. S. Craxton, A. K. Davis, J. A. Delettrez, D. H. Edgell, R. Epstein, M. Farrell, C. J. Forrest, J. A. Frenje, D. H. Froula, M. Gatu Johnson, C. Gibson, V. Yu. Glebov, A. Greenwood, D. R. Harding, M. Hohenberger, S. X. Hu, H. Huang, J. Hund, I. V. Igumenshchev, D. W. Jacobs-Perkins, R. T. Janezic, M. Karasik, R. L. Keck, J. H. Kelly, T. J. Kessler, J. P. Knauer, T. Z. Kosc, S. J. Loucks, J. A. Marozas, F. J. Marshall, R. L. McCrory, P. W. McKenty, D. D. Meyerhofer, D. T. Michel, J. F. Myatt, S. P. Obenschain, R. D. Petrasso, N. Petta, P. B. Radha, M. J. Rosenberg, A. J. Schmitt, M. J. Schmitt, M. Schoff, W. Seka, W. T. Shmayda, M. J. Shoup, A. Shvydky, A. A. Solodov, C. Stoeckl, W. Sweet, C. Taylor, R. Taylor, W. Theobald, J. Ulreich, M. D. Wittman, K. M. Woo, J. D. Zuegel
Initial target physics experiments have been conducted on OMEGA to examine the hydrodynamic mixing seeded by laser imprint, the target-mounting stalk, and microscopic surface debris. As shown in Fig. 5a, a trace amount of Ge (0.7% atomic) was added to the plastic ablator to track hydrodynamic mixing of the ablator through the DT ice layer by the ablation-front instability and into the hot-spot region as illustrated in Fig. 5b. If Ge reaches the hot spot, it will emit K-shell emission.28 A time-integrated, spatially resolved X-ray spectrum of the Ge Heα and satellite emission at ~10 keV of photon energy was recorded as shown in Fig. 5c. This measurement experimentally confirms that the ablator material is mixing into the hot spot. The hot-spot mix mass inferred from the Ge Heα and satellite emission will be used to constrain the simulations and refine the target requirements, similar to target physics experiments conducted on the NIF (Refs. 29 and 30). Although this technique can detect levels of Ge-doped CH to the nanogram-level, it is only sensitive to mass from the Ge-doped ablator. It cannot detect any DT mass that has mixed into the hot spot. In future experiments the absolute X-ray power radiated by the hot spot will be monitored and compared to the neutron yield to infer the amount of total mix mass in the hot spot,31–33 and the effects of a fill tube on implosion performance will be investigated.
The study of fatty acid mediated Mefp-1 adsorption by Quartz Crystal Microbalance with Dissipation
Published in The Journal of Adhesion, 2023
LinQing Xie, Wei Cao, ChengJun Sun
In this study, we used an interface chemical analysis tool-Quartz Crystal Microbalance with Dissipation (QCM-D)[16] to explore the specific functions of fatty acids in the wet adhesion process of mussels. The core of the QCM system is a quartz crystal sensor. When a voltage is applied across the sensor, the quartz crystal will cause a small shear vibration at the resonance frequency.[17] If a substance is adsorbed onto the crystal surface, the vibration of the crystal will be weakened. The decrease in vibration frequency can reflect the thickness and mass of the adsorbed substance with a measurement accuracy reaching nanogram level.[18] We simulated the microenvironment of the mussel adhesion interface by using different substrates. After flowing buffer through the system, fatty acid and Mefp-1 were sequentially flowed through the substrate surface to simulate the dynamic adhesion of Mefp-1. Since C16:0 is one of the major fatty acid involved in the mussel adhesion, we selected palmitic acid as representative C16:0 fatty acid to study its effect on Mefp-1 adhesion. The changes of harmonic frequency and energy dissipation during the adsorption process of Mefp-1 in the presence of fatty acid were monitored by QCM-D. The adsorption mass and thickness of Mefp-1 on the substrate surface were evaluated based on frequency (Δf) and dissipative (ΔD) shift.[19] We hope to answer these two questions: 1) How would different surface properties affect Mefp-1 adhesion, 2) Do fatty acids affect the adhesion of Mefp-1 on different substrates and to what extend if the answer is yes. By studying the role of fatty acids in the dynamic adhesion of Mefp-1, we can better understand mussel adhesion mechanism. Results from this study can provide theoretical support for the research on preventing mussel fouling and biomimetic adhesion materials.