Dual emissive amphiphilic carbon dots as ratiometric fluorescent probes for the determination of critical micelle concentration of surfactants

The sensitive determination of critical micelle concentration (CMC) of surfactants is very important for their practical applications. For the good sensitivity and simple operation, pyrene and its derivatives had been...

One-Pot Solvent-and Catalyst-Free Synthesis of Some New Heteroarylaminonaphthoquinones from Lawsone

: A clean and efficient one-pot protocol for the synthesis of a series of new 2-hydroxy-3-((3-aryl)(heteroarylamino)methyl)naphthalene-1,4-dione derivatives has been developed by the three-component reaction of 2-hydroxynaphthalene-1,4-dione, aromatic aldehydes and heterocyclic amines at 90 oC under solvent and catalyst-free conditions. The procedure avoids the use of toxic solvents, tedious work-up, catalyst and purification of the products by chromatographic methods. Simple operation, short reaction times, generating the desired compounds in high to excellent yields and an environmentally benign method are advantages of this protocol.

Study of the Three-Component Reactions of 2-Alkynylbenzaldehydes, Aniline, and Dialkyl Phosphites—The Significance of the Catalyst System

New, practical approaches for the synthesis of α-amino (2-alkynylphenyl)-methylphosphonates and 1,2-dihydroisoquinolin-1-ylphosphonates were developed. By the propylphosphonic anhydride (T3P®)-mediated Kabachnik–Fields reaction of 2-alkynylbenzaldehydes, aniline, and dialkyl phosphites, α-amino (2-alkynylphenyl)-methylphosphonates were obtained selectively in high yields. The method developed is a simple operation and did not require a chromatographic separation since the products could be isolated from the reaction mixture by a simple extraction. At the same time, 2,3-disubstituted-1,2-dihydroisoquinolin-1-ylphosphonates could be prepared effectively from the same kinds of starting materials (2-alkynylbenzaldehydes, aniline, and dialkyl phosphites) at 60 °C in a short reaction time by changing the catalyst for CuCl. Therefore, it was proved that the catalyst system applied played a crucial role with respect to the reaction outcome.

The Application of Vaginal Color Ultrasound in the Diagnosis and Treatment of Ectopic Pregnancy

To explore the application of vaginal color ultrasound in the diagnosis and treatment of ectopic pregnancy. Methods: From August 2018 to May 2019, 90 patients with suspected ectopic pregnancy who were treated in our hospital were selected as the study objects. Abdominal color ultrasound and vaginal ultrasound were performed respectively to compare the diagnosis results of the two methods. Result: The detection rate of transvaginal ultrasound was higher than that of abdominal ultrasound (P < 0.05); the accuracy rate of transvaginal ultrasound was significantly higher than that of abdominal ultrasound (P < 0.05); the main parts of ectopic pregnancy were ampulla, isthmus and umbrella, and the main types were ruptured, unruptured and obsolete. Conclusion: The application of transvaginal ultrasound in the diagnosis of ectopic pregnancy has the advantages of high accuracy and detection rate, fast examination speed, simple operation, etc. it is of great significance to retain the fertility of patients and is wworthy popularizing.

KOMBINASI CAESAR CIPHER DAN REVERSE CIPHER BERDASARKAN CIPHER BLOCK CHAINING

Communication in the current era of globalization is very developed. Many applications that can be used to facilitate communication. However, because of this convenience, the security of the information contained in it will be more easily hacked by irresponsible people. Cryptography is the science or art for security message. In cryptography there are two important processes, namely encryption and decryption. The sender's job is to encrypt the message and the receiver's job is to decrypt the message. The key used for this cryptographic process is the Cipher Block Chaining (CBC) operation mode. CBC mode is a very simple operation mode, so additional techniques are needed to make it more secure. The plaintext will be replaced with new plaintext resulting from a combination of Caesar Cipher and Reverse Cipher techniques. The results obtained indicate that the application of plaintext modifications to CBC can improve message security because the keys used are increasingly complex.

A novel methodology for the efficient synthesis of 3-monohalooxindoles by acidolysis of 3-phosphate-substituted oxindoles with haloid acids

A novel method for the synthesis of 3-monohalooxindoles by acidolysis of isatin-derived 3-phosphate-substituted oxindoles with haloid acids was developed. This synthetic strategy involved the preparation of 3-phosphate-substituted oxindole intermediates and SN1 reactions with haloid acids. This new procedure features mild reaction conditions, simple operation, good yield, readily available and inexpensive starting materials, and gram-scalability.

The Efficient Synthesis of 2-(3-Carbamoylpyridine-2-yl) nicotinamide Pyridine Salts

: The synthesis of axially chiral compounds has attracted a great deal of attention in the recent years. Herein, an efficient and economical synthetic route has been developed for 2-(3-carbamoylpyridin-2-yl) nicotinamide pyridine salts, an axially chiral compound. The starting material 1,10-phenanthroline has been readily available and 2-(3-carbamoylpyridin-2-yl) nicotinamide pyridine salts have been obtained in moderate to good yields. This protocol features simple operation and easy scalability. In addition, the axial chirality of the products has also been preliminary studied.

Passively Driven Microfluidic Device with Simple Operation for Quantitative Droplet LAMP Sssay for Point-of-Care Analysis

Since polymerase chain reaction (PCR) has become a vital tool for disease diagnosis, the development of precise applied PCR technologies in point-of care testing (POCT) has become more significant. The microfluidic-based PCR platform offers a great opportunity for on-site diagnosis efficiency, and the system is aimed at user-friendly access. Herein, we demonstrate a microfluidic system with simple operation that provides reliable nucleic acid results from 18 uniform droplets via LAMP qPCR detection. By using only micropipette regulation, users are able to control the nanoliter scale of the droplets in this valve-free and pump-free microfluidic (MF) chip. Based on the oil enclosure method and impermeable fabrication, we successfully preserved the reagent inside the microfluidic system, which significantly reduced the fluid loss and condensation. The relative standard deviation (RSD) of the fluorescence intensity between the droplets and during the heating process was <5% and 2.0%, respectively. Additionally, for different nucleic acid detection methods, the MF-LAMP chip in this study showed good applicability to both genome detection and gene expression analysis.

Oxidative Dimerization of 1Н-Benzo[f]chromenes: Synthesis of Benzannulated Analogues of Spirobiflavonoids Welwitschins E and F

A new oxidative transformation of 1H-benzo[f]chromenes into spirodimers under the action of selenium dioxide was discovered, leading to spirodimers, which are dibenzannulated analogues of naturally occurring welwitschins E and F. In the reaction, both MnO2 and I2O5 can also be used as an oxidant. The protocol has advantages of mild reaction conditions and simple operation. At the same time, oxidation of 1H-benzo[f]chromenes with (diacetoxyiodo)benzene is accompanied by the formation of 3,3′-bibenzo[f]chromene as a dimer of a different structure. It was also found that 4H-chromenes under the action of various oxidants are cleaved to give chalcone.

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

An efficient and convenient method for the synthesis of structurally unique and highly functionalized aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers has been developed. This approach exhibits a broad reaction scope, a simple operation and without the need of any expensive transition-metal catalyst, highly toxic or corrosive reagents. Notably, we demonstrate the potential utility of halothane for the synthesis of aryl gem-difluoroalkyl ethers containing the bromochloromethyl group.