Synthetic Technology Research Articles

Characterization on the occurrence state of nitrogen getter Ti in HPHT grown synthetic diamond crystals

Type IIa diamonds are the most promising gem grade, optical and electronic grade materials with high quality and low defects, however natural type IIa diamonds are rare and therefore the synthetic methods to obtain the high quality type IIa diamonds have been a hot issue. Nitrogen getters play a crucial role in the synthesis of type IIa high temperature high pressure (HPHT) diamonds crystals by reacting with the nitrogen in the system and effectively removing it from the growth process. However, the occurrence state of nitrogen getter introduced after diamond crystal growth remains to be investigated. In this study, a group of HPHT synthetic diamond crystals with different mass fractions of Ti as a nitrogen getter were examined by scanning electron microscopy coupled with energy dispersive spectrometer (SEM-EDS) and X-ray fluorescent spectroscopy (micro-XRF) to observe the occurrence state of the nitrogen getter Ti within the synthetic diamond crystal, it was found that at the end of crystal growth, There are two forms of Ti present in the process: (i) Ti reacts with C to form TiC, which was deposited on the surface of the diamond crystal in the dendritic pattern, and (ii) Ti enters the diamond crystal to form metallic inclusions. This study provides reliable data to support a comprehensive analysis of the effect of Ti as a nitrogen getter in the growth procession of HPHT synthetic diamond crystal, and it will have a positive effect on the development of synthetic diamond technology.

Research on Photoacoustic Synthetic Aperture Focusing Technology Imaging Method of Internal Defects in Cylindrical Components.

Cylindrical components are parts with curved surfaces, and their high-precision defect testing is of great significance to industrial production. This paper proposes a noncontact internal defect imaging method for cylindrical components, and an automatic photoacoustic testing platform is built. A synthetic aperture focusing technology in the polar coordinate system based on laser ultrasonic (LU-pSAFT) is established, and the relationship between the imaging quality and position of discrete points is analyzed. In order to verify the validity of this method, small holes of Φ0.5 mm in the aluminum alloy rod are tested. During the imaging process, since a variety of waveforms can be excited by the pulsed laser synchronously, the masked longitudinal waves reflected by small holes need to be filtered and windowed to achieve high-quality imaging. In addition, the influence of ultrasonic beam angle and signal array spacing on imaging quality is analyzed. The results show that the method can accurately present the outline of the small hole, the circumferential resolution of the small hole is less than 1° and the dimensional accuracy and position error are less than 0.1 mm.

Pd/Co2(CO)8‐mediated bi‐metallic catalysis: Facile synthesis of pharmacologically relevant novel tacrine analogues

AbstractFacile synthesis of amino/alkoxy/hydroxy‐carbonylated tacrine analogues by employing Pd/Co2(CO)8 mediated bimetallic catalysis is reported herein. A wide variety of amides and esters have been successfully incorporated at C‐6 of the tacrine core by employing this useful synthetic technology. The major highlight of this methodology includes the use of cobalt carbonyl in catalytic amounts to enhance the efficiency of the overall reaction.

Surface defects detection in metal materials repaired by laser surfacing of seal welds

Laser surfacing repair technology for sealing welds is widely used in metal repair. Due to welding technology and usage scenarios, process defects on the metal surface are inevitable. Therefore, ultrasonic surface wave technology is used to analyze the surface defects of metal materials. Principal Component Analysis (PCA) is used to extract the main defect signals on the metal surface, and synthetic aperture focusing technology is used to reduce imaging errors. Considering the lack of PCA in imaging defects, wavelet domain hidden Markov models (WHMM) are combined to optimize the signal, thereby improving the inspection effect of metal defects. In the test results of the relationship between the propagation distance of 316 L steel and the defect echo signal, the echo signal gradually fitted as the propagation distance increased. When the propagation distance was greater than 10 mm, the image acquisition defect signal had significant noise points. Various techniques were used to process the original echo signals of metal surface defects. The improved PCA-WHMM algorithm had significant advantages with the SNR value of the defect image increased by 13.65 % compared to PCA-WHMM. At the same time, the surface repair effects of laser surfacing 316 L metal before and after optimization were compared. The hardness, toughness, and corrosion resistance of the optimized metal were significantly improved. The proposed technological innovation combines traditional laser surfacing repair with deep learning fault diagnosis, which not only greatly improves the efficiency of fault diagnosis, but also proves that this research can effectively avoid common focus issues of laser surfacing repair technology, providing important technical reference for the application of ultrasonic technology in metal defect detection.

Electrochemical flow aziridination of unactivated alkenes.

Aziridines derived from bioactive molecules may have unique pharmacological activities, making them useful in pharmacology (e.g. mitomycin C). Furthermore, the substitution of the epoxide moiety in epothilone B with aziridine, an analog of epoxides, yielded a pronounced enhancement in its anticancer efficacy. Thus, there is interest in developing novel synthetic technologies to produce aziridines from bioactive molecules. However, known methods usually require metal catalysts, stoichiometric oxidants and/or pre-functionalized amination reagents, causing difficulty in application. A practical approach without a metal catalyst and extra-oxidant for the aziridination of bioactive molecules is in demand, yet challenging. Herein, we report an electro-oxidative flow protocol that accomplishes an oxidant-free aziridination of natural products. This process is achieved by an oxidative sulfonamide/alkene cross-coupling, in which sulfonamide and alkene undergo simultaneous oxidation or alkene is oxidized preferentially. Further anticancer treatments in cell lines have demonstrated the pharmacological activities of these aziridines, supporting the potential of this method for drug discovery.

Guest editorial: recent advances in synthetic aperture sonar technology

Abstract[Correction added on 28‐July‐2023, after first online publication: The first affiliation has been changed and bio for Gary Heald has been added in this version.]Compared to traditional sidescan sonar, synthetic aperture sonar (SAS) or Interferometric synthetic aperture sonar (InSAS) systems can provide much higher resolution images across the whole swath. Due to the high resolution and fast mapping rate at a given speed, SAS/InSAS technology is gaining increasing interest within the field of underwater engineering. Navigation, autonomous underwater vehicles (AUVs), sonar technolog and electronics have achieved great progress in recent years. Thanks to these developments, the SAS/InSAS has also been pushed into a new stage. Firstly, the lightweight and compact SAS can be mounted on ever smaller, highly flexible platforms. Secondly, current algorithms are computationally more efficient. Thirdly, the SAS/InSAS images are further improved based on various methods. Last but not least, SAS/InSAS technology is preferred by underwater mapping users due to its high resolution. The current Special Issue is focused on research ideas, articles and experimental studies related to “Recent Advances in Synthetic Aperture Sonar Technology” for development, operating mode, algorithms and applications the various aspects of SAS/InSAS in applications.

Advances in processing, encapsulation, and analysis of food flavor compounds

AbstractIn recent years, the market for edible flavor has become larger and the demand for edible flavor has become more diverse. Customers are paying more attention to natural, healthy, and functional flavors. This article reviews some new technologies about flavors in recent years, including processing technology, encapsulation, and detection of flavors. The synthetic technologies of flavor include thermal reaction technology, enzymatic hydrolysis technology, and microbial fermentation technology. The encapsulation technology includes nano‐emulsion and filled soluble hydrogel, as well as the new carrier materials used in packaging, such as β‐cyclodextrin, 2‐acetyl‐1‐pyrroline (2AP), yeast cell, and jackfruit seed starch (JM) are also hot spots in recent years. Finally, the detection of flavor components and the monitoring of characteristic flavor substances and harmful flavor substances are very important for flavor quality control. There are many detection techniques, such as chromatographic analysis techniques, solid‐phase microextraction, electronic nose and electronic tongue, sensor arrays, and fluorescence detection with DNA barcoding techniques and (quantitative) conformational relationships.

Advances on the production of organic acids by yeast

Organic acids are organic compounds that can be synthesized using biological systems. They often contain one or more low molecular weight acidic groups, such as carboxyl group and sulphonic group. Organic acids are widely used in food, agriculture, medicine, bio-based materials industry and other fields. Yeast has unique advantages of biosafety, strong stress resistance, wide substrate spectrum, convenient genetic transformation, and mature large-scale culture technology. Therefore, it is appealing to produce organic acids by yeast. However, challenges such as low concentration, many by-products and low fermentation efficiency still exist. With the development of yeast metabolic engineering and synthetic biology technology, rapid progress has been made in this field recently. Here we summarize the progress of biosynthesis of 11 organic acids by yeast. These organic acids include bulk carboxylic acids and high-value organic acids that can be produced naturally or heterologously. Finally, future prospects in this field were proposed.

Synthetic aperture radar radio frequency interference suppression technology

Radio frequency interference (RFI) can easily hinder the data collection, imaging and interpretation of the initial echo of synthetic aperture radar, which has always been a difficult problem affecting the accuracy of synthetic aperture radar. In this paper, the radio frequency interference suppression technology of synthetic aperture radar is analyzed and studied. It can be concluded that in todays complex and changeable electromagnetic environment, although many literature have proposed and established different objective functions and constraints for more specific application environments, there is still room for further improvement. Therefore, the future SAR system needs to select the most appropriate interference suppression method according to the dynamic changes of RFI environment. The development trend of interference suppression technology in the future is obtained from the comprehensive analysis of the RFI interference sources, RFI models and existing SAR interference suppression technologies, which provides a certain reference for future research.

A Robust and Efficient DNA Storage Architecture Based on Modulation Encoding and Decoding.

Synthetic DNA has been widely considered an attractive medium for digital data storage. However, the random insertion-deletion-substitution (IDS) errors in the sequenced reads still remain a critical challenge to reliable data recovery. Motivated by the modulation technique in the communication field, we propose a new DNA storage architecture to solve this problem. The main idea is that all binary data are modulated into DNA sequences with the same AT/GC patterns, which facilitate the detection of indels in noisy reads. The modulation signal could not only satisfy the encoding constraints but also serve as prior information to detect the potential positions of errors. Experiments on simulation and real data sets demonstrate that modulation encoding provides a simple way to comply with biological constraints for sequence encoding (i.e., balanced GC content and avoiding homopolymers). Furthermore, modulation decoding is highly efficient and extremely robust, which can correct up to ∼40% of errors. In addition, it is robust to imperfect clustering reconstruction, which is very common in practice. Although our method has a relatively low logical density of 1.0 bits/nt, its high robustness may provide a wide space for developing low-cost synthetic technologies. We believe this new architecture may boost the early coming of large-scale DNA storage applications in the future.

Applications of Flow Chemistry in Total Synthesis of Natural Products

Abstract: A vital driving force for chemists to discover novel synthetic protocols is the improvement of more effective synthetic technologies and sustainable methodologies. This is associated with the development of innovative research that stimulates the creative reevaluating of known conceptions. Currently, these robust methodologies, as well as green synthetic procedures, have been designed for the total synthesis of secondary metabolites. Flow chemistry and flow photochemistry have emerged as powerful tools to promote valuable transformations in the total synthesis of natural products as key step(s). Flow chemistry development offers many merits over a traditional batch format, namely a round-bottom flask. The advantages of this green tool comprise waste minimization, simple scale-up, reduction of reaction time, safety betterment as, well as energy and cost efficiency. Flow chemistry comprises a fascinating prospect for the synthesis of promising organic molecules and bioactive complex natural products as it represents a suitable modern synthetic technology for the improvement of sustainable chemistry. Continuous flow chemistry is an assembly of chemical processes carried out in continuous flowing streams. Compared to conventional organic synthesis, it is a process that strengthens technology and is superior in enhancing and scaling up synthesis, accurately controlling reaction rate, and providing the desired products with maximum yields. In the past and likely in the future natural products and their analogue will continue to deliver the stimulation for drug discovery and development programs. Total synthesis of natural products is very useful to synthesize natural products in the laboratory as many secondary metabolites are available in low quantities from their sources of origin. So, this review wishes to cover the brilliant applications of flow chemistry in the total synthesis of natural products in the field of novel technological advances.

Optical Bioimaging and Therapy

Optical Bioimaging and Therapy

Communication and Perception of Emerging Science, Technology and Innovation in Nigeria: Implications for Development

There is a paucity of empirical research on emerging Science, Technology, and Innovation (STI) communication in Nigeria, and the impact on national development. This study sought answers to: what are the perceptions of emerging STI among Nigerian citizens and academics, and to what extent do emerging STIs contribute to national development? Based on the science-technology-society theory, the study conducted a survey of 2400 Nigerians in 12 states and an interview of select STI experts in 12 Nigerian universities. The study focused on synthetic biology, nanoscience and technology, robotics and artificial intelligence, drones, etc. The findings showed that a greater majority of the respondents perceived agricultural drones as the most necessary emerging STI in Nigeria while neuroparasitology was seen as the least necessary to the country’s development. Respondents also agreed that emerging STI had the more impact on ICTs and the least on security, economy and the environment. Also, large segment of respondents perceived that the new/ mass media were the predominant sources of emerging STI information. Also, STI experts perceived emerging STIs to be in their infancy in Nigeria, communication of STIs was concentrated within the scientific community, and collaboration was lacking between the STI community and other stakeholders.

Polymer Semiconductors: Synthesis, Processing, and Applications.

Polymer semiconductors composed of a carbon-based π conjugated backbone have been studied for several decades as active layers of multifarious organic electronic devices. They combine the advantages of the electrical conductivity of metals and semiconductors and the mechanical behavior of plastics, which are going to become one of the futures of modulable electronic materials. The performance of conjugated materials depends both on their chemical structures and the multilevel microstructures in solid states. Despite the great efforts that have been made, they are still far from producing a clear picture among intrinsic molecular structures, microstructures, and device performances. This review summarizes the development of polymer semiconductors in recent decades from the aspects of material design and the related synthetic strategies, multilevel microstructures, processing technologies, and functional applications. The multilevel microstructures of polymer semiconductors are especially emphasized, which plays a decisive role in determining the device performance. The discussion shows the panorama of polymer semiconductors research and sets up a bridge across chemical structures, microstructures, and finally devices performances. Finally, this review discusses the grand challenges and future opportunities for the research and development of polymer semiconductors.

Prediction of Mine Subsidence Based on InSAR Technology and the LSTM Algorithm: A Case Study of the Shigouyi Coalfield, Ningxia (China)

The accurate prediction of surface subsidence induced by coal mining is critical to safeguarding the environment and resources. However, the precision of current prediction models is often restricted by the lack of pertinent data or imprecise model parameters. To overcome these limitations, this study proposes an approach to predicting mine subsidence that leverages Interferometric Synthetic Aperture Radar (InSAR) technology and the long short-term memory network (LSTM). The proposed approach utilizes small baseline multiple-master high-coherent target (SBMHCT) interferometric synthetic aperture radar technology to monitor the mine surface and applies the long short-term memory (LSTM) algorithm to construct the prediction model. The Shigouyi coalfield in Ningxia Province, China was chosen as a study area, and time series ground subsidence data were obtained based on Sentinel-1A data from 9 March 2015 to 7 June 2016. To evaluate the proposed approach, the prediction accuracies of LSTM and Support Vector Regression (SVR) were compared. The results show that the proposed approach could accurately predict mine subsidence, with maximum absolute errors of less than 2 cm and maximum relative errors of less than 6%. The findings demonstrate that combining InSAR technology with the LSTM algorithm is an effective and robust approach for predicting mine subsidence.

Electric‐Field‐Induced Organic Transformations

AbstractExperiments showed that the existence of electric fields in non‐redox processes may alter the catalytic activity, rate enhancement, and selection of organic reactions. It is expected that the interaction between electric fields and chemical reactions will create new avenues for producing materials with desired properties in several chemical disciplines, including synthetic organic chemistry, catalysis, nanotechnology, membrane technology, and enzyme catalysis. Specifically, in this review, we discuss the elegant experimental investigations carried out using the scanning tunneling microscope, the interfacial electric field, and designed local electric fields. The results of these studies are remarkable, leading to new information on the function of electric fields in controlling chemical reactivity and selectivity in different reactions and offering a glimpse of the great potential of electrostatic fields. This article not only presents the core concepts of field‐induced chemical transformations but also illustrates the potential use of electric field catalysis in chemistry and other fields.

Application of Synthetic Biology in SARS-CoV-2 Vaccine Development

The novel coronavirus SARS-CoV-2 has been spreading at an extraordinary rate since it first appeared in late 2019, causing a large number of infections and deaths. The COVID-19 pan-demic can be successfully controlled most effectively with vaccines, and efforts are being made globally to create new vaccines. Synthetic biology is a design-oriented field that focus-es on creating novel biological functions by discovering, analyzing, and repurposing biologi-cal components. Many SARS-CoV-2 vaccines have been developed using synthetic biology, and the recent approval of a few more vaccines is evidence of the field's continuous growth. This review discusses the use of synthetic biology technology in the creation of several COVID-19 vaccines, concentrating on how to produce vaccines that are safer and more effec-tive through genome optimization and delivery mechanism optimization. Finally, this article highlights some existing problems of synthetic biology technology and provides an outlook on the future development of application this technology in COVID-19 vaccines.

CHO synthetic promoters improve expression and product quality of biotherapeutic proteins.

When expressing complex biotherapeutic proteins, traditional expression plasmids and methods may not always yield sufficient levels of high-quality product. High-strength viral promoters commonly used for recombinant protein (rProtein) production in mammalian cells allow for maximal expression, but provide limited scope to alter their transcription dynamics. However, synthetic promoters designed to provide tunable transcriptional activity offer a plasmid engineering approach to more precisely regulate product quality, yield or to reduce product related contaminants. We substituted the viral promoter CMV with synthetic promoters that offer different transcriptional activities to express our gene of interest in Chinese hamster ovary (CHO) cells. Stable pools were established and the benefits of regulating transgene transcription on the quality of biotherapeutics were examined in stable pool fed-batch overgrow experiments. Specific control of gene expression of the heavy chain (HC):light chain (LC) of a Fab, and the ratio between the two HCs in a Duet mAb reduced levels of aberrant protein contaminants; and the controlled expression of the helper gene XBP-1s improved expression of a difficult-to-express mAb. This synthetic promoter technology benefits applications that require custom activity. Our work highlights the advantages of employing synthetic promoters for production of more complex rProteins.

Strategies for Nucleophilic C(sp3)-(Radio)Fluorination.

This Perspective surveys the progress and current limitations of nucleophilic fluorination methodologies. Despite the long and rich history of C(sp3)-F bond construction in chemical research, the inherent challenges associated with this transformation have largely constrained nucleophilic fluorination to a privileged reaction platform. In recent years, the Doyle group─along with many others─has pursued the study and development of this transformation with the intent of generating deeper mechanistic understanding, developing user-friendly fluorination reagents, and contributing to the invention of synthetic methods capable of enabling radiofluorination. Studies from our laboratory are discussed along with recent developments from others in this field. Fluoride reagent development and the mechanistic implications of reagent identity are highlighted. We also outline the chemical space inaccessible by current synthetic technologies and a series of future directions in the field that can potentially fill the existing dark spaces.

An image cryptography method by highly error-prone DNA storage channel.

Introduction: Rapid development in synthetic technologies has boosted DNA as a potential medium for large-scale data storage. Meanwhile, how to implement data security in the DNA storage system is still an unsolved problem. Methods: In this article, we propose an image encryption method based on the modulation-based storage architecture. The key idea is to take advantage of the unpredictable modulation signals to encrypt images in highly error-prone DNA storage channels. Results and Discussion: Numerical results have demonstrated that our image encryption method is feasible and effective with excellent security against various attacks (statistical, differential, noise, and data loss). When compared with other methods such as the hybridization reactions of DNA molecules, the proposed method is more reliable and feasible for large-scale applications.