The interactions (including weak interactions) between dienophiles and dienes play an important role in the Diels-Alder reaction. To elucidate the influence of these interactions on the reactivity, a popular DFT functional and a variational DFT functional corrected with dispersion terms are used to investigate different substituent groups incorporated on the dienophiles and dienes. The bond order is used to track the trajectory of the cycloaddition reaction. The deformation/interaction model is used to obtain the interaction energy from the reactant complex to the inflection point until reaching the saddle point. The interaction energy initially increases with a decrease in the interatomic distance, reaching a maximum value, but then decreases when the dienophiles and dienes come closer. Reduced density gradient and chemical energy component analysis are used to analyse the interaction. Traditional transition state theory and variational transition state theory are used to obtain the reaction rates. The influence of tunneling on the reaction rate is also discussed.

Zhiling Liang

Houhe Liu

Nianjun Su

Dandan Song

Yun Zhang

Hong Huang

Jianqi Zheng

Cheng Zhong

Guodong Ye

Study of the Deformation/Interaction Model: How Interactions Increase the Reaction Barrier

Nanopowders of copper indium diselenide were produced with five different organic solvents: ethylenediamine, triethanolamine, oleylamine, oleic acid, and polyetheramine. We successfully synthesized pure CIS nanopowders at a temperature of 240&#xb0;C at three different durations of 10&#x2009;h, 20&#x2009;h, and 40&#x2009;h with a one-step process. This shorter time method offers important cost advantages in manufacturing. Polyetheramine and oleic acid were used for the first time in literature for CIS synthesis in an autoclave.

Ali Murat Soydan

Pinar Yilmaz

Bahad&#x131;r Tunaboylu

Synthesis of CIS (CuInSe2) Based Materials for Solar Applications

This paper attempts to evaluate the Malaysian water quality indexing method that has been criticized for its ineffectiveness. The indexing method is referred to as the Water Quality Index of the Department of Environment, Malaysia (DOE-WQI). This index was assessed against two other indices (River Ganga Index and Minimal Water Quality Index <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.18147pt" id="M1" height="12.4698pt" version="1.1" viewBox="-0.0498162 -9.28833 51.0859 12.4698" width="51.0859pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-41" d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"/></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path id="g121-85" d="M956 650H736V622C814 613 818 602 804 542C789 471 733 275 691 141H689C628 314 570 476 514 641H485C434 478 377 312 323 142H321C277 284 238 419 199 554C184 605 186 613 259 622V650H16V622C77 615 92 606 117 524C172 346 228 170 281 -11H312C363 151 419 312 475 488H477C528 343 597 150 652 -11H683C765 269 826 458 848 522C878 605 887 613 956 622V650Z"/></g><g transform="matrix(.013,0,0,-0.013,16.638,0)"><path id="g121-79" d="M720 -138C627 -96 538 -41 476 2C594 39 703 153 703 331C703 532 552 665 384 665C170 665 44 499 44 315C44 215 87 129 147 73C211 11 298 -11 355 -14C476 -99 554 -136 584 -144S664 -160 712 -159L720 -138ZM348 25C231 49 146 172 146 342C146 533 249 629 360 629C497 629 601 510 601 302C601 142 523 51 443 28C434 34 425 41 416 47L348 25Z"/></g><g transform="matrix(.013,0,0,-0.013,26.206,0)"><path id="g121-71" d="M303 0V28C221 34 213 39 213 125V525C213 610 221 616 303 622V650H38V622C120 616 128 610 128 525V125C128 40 120 34 38 28V0H303Z"/></g><g transform="matrix(.0091,0,0,-0.0091,30.739,3.132)"><path id="g58-107" d="M810 0V30C751 35 744 40 744 106V296C744 396 694 451 614 451C583 451 558 438 537 425C512 409 485 391 454 368C434 420 390 451 342 451C309 451 285 439 260 424C228 405 206 387 185 372V453C141 434 90 421 43 413V386C102 378 105 373 105 309V106C105 41 96 35 29 30V0H243V30C194 35 185 41 185 106V335C216 360 256 389 297 389C357 389 384 348 384 275V106C384 41 374 35 312 30V0H530V30C475 35 465 41 465 104V294C465 313 464 324 463 336C502 367 539 389 576 389C637 389 663 346 663 274V109C663 41 653 35 593 30V0H810Z"/></g><g transform="matrix(.0091,0,0,-0.0091,38.328,3.132)"><path id="g58-103" d="M138 535C169 535 191 560 191 589C191 620 168 644 139 644S85 620 85 589C85 560 110 535 138 535ZM257 0V30C192 35 185 43 185 109V453C142 435 94 422 40 414V386C101 378 104 372 104 311V109C104 41 97 35 33 30V0H257Z"/></g><g transform="matrix(.0091,0,0,-0.0091,40.831,3.132)"><path id="g58-108" d="M532 0V30C473 38 467 38 467 107V298C467 395 416 451 336 451C307 451 279 439 251 420C226 404 205 389 185 374V453C142 434 94 422 43 413V386C98 378 104 373 104 309V107C104 41 100 38 31 30V0H251V30C191 35 185 40 185 107V337C216 364 255 389 295 389C360 389 386 347 386 276V110C386 44 380 35 321 30V0H532Z"/></g><g transform="matrix(.013,0,0,-0.013,46.454,0)"><path id="g113-42" d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"/></g></svg>) and a modified DOE-WQI was also proposed. DOE-WQI and <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.181499pt" id="M2" height="11.9479pt" version="1.1" viewBox="-0.0498162 -8.7664 42.0562 11.9479" width="42.0562pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g121-85"/></g><g transform="matrix(.013,0,0,-0.013,12.14,0)"><use xlink:href="#g121-79"/></g><g transform="matrix(.013,0,0,-0.013,21.708,0)"><use xlink:href="#g121-71"/></g><g transform="matrix(.0091,0,0,-0.0091,26.241,3.132)"><use xlink:href="#g58-107"/></g><g transform="matrix(.0091,0,0,-0.0091,33.83,3.132)"><use xlink:href="#g58-103"/></g><g transform="matrix(.0091,0,0,-0.0091,36.333,3.132)"><use xlink:href="#g58-108"/></g></svg> are physicochemical indices, whereas the River Ganga Index and modified DOE-WQI are indices with the inclusion of a microbiological parameter. The assessment was conducted based on the water quality of tropical rivers in Malaysia, with specific reference to Sarawak River and its tributaries. Water quality in terms of pH, dissolved oxygen, conductivity, turbidity, total suspended solids, biochemical oxygen demand, chemical oxygen demand, ammoniacal nitrogen, and fecal coliform count (FCC) was measured from 18 stations in December 2015, January 2016, and March 2016. Generally, the river was characterized with high FCC with the four indices significantly correlated. The results demonstrated the shortcomings of the existing DOE-WQI; the physicochemical index assigned water quality to a better class than its actual conditions without taking into consideration the FCC.

Siong Fong Sim

Szewei Elaine Tai

Assessment of a Physicochemical Indexing Method for Evaluation of Tropical River Water Quality

Deep eutectic solvents (DESs) have attracted significant attention as green media for the extraction and separation of natural compounds from Chinese medicine. In this study, a hydrophobic DESs-based microwave-assisted extraction (MAE) was successfully used to efficiently extract baicalin from Scutellaria baicalensis Georgi. Firstly, DecA: N4444-Cl (DES-1 , molar ratio 1&#x2009;:&#x2009;2) was screened and selected as the most appropriate DES by comparing the extraction yield in different hydrophobic DESs. Based on the extraction yield of baicalin, response surface methodology (RSM) was employed to model and optimize the parameters (extraction temperature, liquid-solid ratio, and extraction time). Furthermore, the maximum yield of 106.96&#x2009;mg&#xB7;g&#x2212;1 was achieved under optimum conditions in DES-containing aqueous solutions (33 vol&#x25; water content), which reached a similar level that was conducted using the pharmacopoeia procedure (104.94&#x2009;mg&#xB7;g&#x2212;1). These results indicated that the proposed method is an excellent alternative for the extraction of baicalin.

Hui Wang

Xiaodi Ma

Qibin Cheng

Xiaoli Xi

Liwei Zhang

Deep Eutectic Solvent-Based Microwave-Assisted Extraction of Baicalin from Scutellaria baicalensis Georgi

The main concern of this work was to find a new biological antisprouting product for potatoes during storage. Ruta chalepensis L. essential oil (RCEO) was for the first time used as a potential sprouting inhibitor for potatoes. To confirm RCEO antisprouting effect, evolution of sprout length and weight loss of potato tubers was determined during a storage period of six weeks under three RCEO different treatments (2&#x25;, 4&#x25;, and 6&#x25;). Sprout final weight was also computed. Then, a screening of RCEO chemical composition was performed. An outstanding antisprouting effect of 6&#x25; emulsions concentrations was observed as compared to 2&#x25; and 4&#x25; emulsions concentrations. Final sprout weight (SW) of untreated samples was 4.66&#x25;, while 6&#x25; treated samples scored 0.98&#x25;. These results were endorsed by high Pearson correlation coefficients (&#x3e;0.9). Indeed, increasing treatment concentration enhanced the sprout growth inhibition. Identification of RCEO major components showed that 2-undecanone represented 87.18&#x25; of total identified components suggesting that this component is the possible active agent of RCEO against potatoes sprouting.

Olfa Lengliz

Jamel Mejri

Manef Abderrabba

Rachid Khalifa

Mondher Mejri

Ruta chalepensis L. Essential Oil: A New Antisprouting Agent for Potatoes Bioconservation

The flotation separation on chlorite and hematite with the new modified fatty acid collector CY-23 was studied. The investigation included both flotation and reagent adsorption tests. And all the characteristics of chlorite surface before and after the adsorption of new collector CY-23 have been studied with X-ray photoelectron spectroscopy (XPS). The flotation results showed that caustic starch (CS) could depress the flotation of hematite and chlorite and CaCl2 could activate chlorite flotation but failed on hematite when using CY-23 as collector. The adsorption rate of CY-23 on the surface of chlorite after being inhibited by CS was relatively smaller, but the amount of CY-23 adsorbed on the inhibited chlorite was greatly increased after adding activator CaCl2. The results of XPS analysis showed that the photoelectron spectroscopy peaks of Mg2p and Al2p moved towards low energy after collector CY-23 was absorbed on chlorite surface, which indicated that chemical bonding through electron cloud transfer occurred between collector CY-23 and Mg, Al ions of chlorite surface. The chemical reaction promoted the adsorption of CY-23 on chlorite surface and eventually improved the ability of CY-23 to float and collect chlorite.

Wenli Jiang

Yulin Zhou

Yimin Zhang

The Effect of New Modified Fatty Acid (CY-23) Collector on Chlorite/Hematite Separation

Analytical Chemistry

Agricultural Chemistry

Environmental Chemistry

Food Chemistry

Geochemistry

Inorganic Chemistry

Medicinal Chemistry

Materials Chemistry

Nuclear Chemistry

Organometallic Chemistry

Organic Chemistry

Physical Chemistry

Petroleum Chemistry

Theoretical Chemistry

biochemistry

About this journal

Journal of Chemistry publishes original research articles as well as review articles on all aspects of fundamental and applied chemistry, including biological, environmental, forensic, inorganic, organic, physical and theoretical.

Journal profile

Meet the editorial board

Journal of Chemistry maintains an Editorial Board of practicing researchers from around the world, to ensure manuscripts are handled by editors who are experts in the field of study.

Editor spotlight

Submit to Special Issue

We currently have a number of Special Issues open for submission. Special Issues highlight emerging areas of research within a field, or provide a venue for a deeper investigation into an existing research area.

Special Issues

Author guidelines

Editorial board

Databases and indexing

Journal of Chemistry - Table of contents 2018

title

Journal of Chemistry publishes original research articles as well as review articles on all aspects of fundamental and applied chemistry, including biological, environmental, forensic, inorganic, organic, physical and theoretical.

Journal of Chemistry