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Hongyan Gao,1 Xiaodi Song,2 Ting Kang,3 Baohong Yan,4 Li Feng,5 Li Gao,6 Liang Ai,6 Xiaoni Liu,7,* Jie Yu,8,* Huiqi Li9,* 1Department of Gastroenterology, The First Affiliated Hospital of Xi’an Medical University, 2Department of Pharmacy, Xi’an Central Hospital, Xi’an, 3Department of Oncology, Yan’an University Affiliated Hospital, Yan’an, 4Department of Pharmacy, Hong-Hui Hospital, Xi’an Jiaotong University Medical College, Xi’an, 5Department of Anorectal Surgery, Ankang City Central Hospital, Ankang, 6Department of Pharmacy, Yan’an University Affiliated Hospital, 7Department of Endocrinology, Yan’an People’s Hospital, Yan’an, 8Department of General Surgery, Nuclear Industry 215 Hospital of Shaanxi Province, Xianyang, 9Department of General Surgery, The People’s Hospital of Baoji City, Baoji, People’s Republic of China *These authors contributed equally to this work Abstract: Colorectal neoplasia differentially expressed (CRNDE) is a novel gene recognized as a long noncoding RNA (lncRNA) that is highly elevated in colorectal cancer and many other solid tumors but its functions on metastasis and oxaliplatin (OXA) resistance are unknown. In our study, we confirmed the upregulation of CRNDE in both primary specimens from colorectal cancer patients and colorectal cancer cell lines. Knockdown of CRNDE expression inhibited the migration and invasion potency of colorectal cancer cells with no effect on cell apoptosis. Overexpression of CRNDE promoted the migration and invasion potency of colorectal cancer cells. Furthermore, we found that CRNDE conferred chemoresistance in colorectal cancer cells. Knockdown of CRNDE with OXA treatment decreased cell viability and promoted DNA damage and cell apoptosis, while the overexpression of CRNDE with OXA treatment reduced DNA damage and cell apoptosis. Further in-depth mechanistic studi

A new helvolic acid derivative named helvolic acid methyl ester (1), together with two known helvolic acid compounds, helvolic acid (2) and hydrohelvolic acid (3), were isolated from the fermentation of endophytic fungus Fusarium sp. in Ficus carica leaves. Their structures were elucidated and identified by spectroscopic methods. Compounds 1–3 showed potent antifungal and antibacterial activities.

Arsenic and zinc are efficiently leached in an alkaline system using air as an oxidant. The results show that the appropriate leaching conditions are listed as follows: the alkali concentration is 5 mol/l, reaction temperature is 80 degrees C, reaction time is 12 h, liquid to solid ratio is 5:1. Under the above conditions, the leaching rate of arsenic and zinc in the residue can reach more than 99% and that of cobalt and copper is below 2%. Nickel is not substantially leached. Its apparent activation energy is 11.62 kJ/mol. It can be seen that the oxidation of arsenic leaching is mainly controlled by diffusion. The average reaction order is 0.69. The leaching residue contains 68.24% Cu, 3.04% Co, 0.87% Ni, and only 0.01% of arsenic. It is conducive to the further recovery of copper, cobalt and nickel. The alkali leaching is a simple and low cost technical operation. The technology avoids the generation of highly toxic AsH3 and has a practical significance for the comprehensive utilisation of arsenic resources., Arsenic and zinc are efficiently leached in an alkaline system using air as an oxidant. The results show that the appropriate leaching conditions are listed as follows: the alkali concentration is 5 mol/l, reaction temperature is 80 degrees C, reaction time is 12 h, liquid to solid ratio is 5:1. Under the above conditions, the leaching rate of arsenic and zinc in the residue can reach more than 99% and that of cobalt and copper is below 2%. Nickel is not substantially leached. Its apparent activation energy is 11.62 kJ/mol. It can be seen that the oxidation of arsenic leaching is mainly controlled by diffusion. The average reaction order is 0.69. The leaching residue contains 68.24% Cu, 3.04% Co, 0.87% Ni, and only 0.01% of arsenic. It is conducive to the further recovery of copper, cobalt and nickel. The alkali leaching is a simple and low cost technical operation. The technology avoids the generation of highly toxic AsH3 and has a practical significance for the comprehensive utilisation of arsenic resources.

A three-step process is described for the deep removal of copper from nickel electrolysis anode solutions comprising the preparation of manganese sulphide from sodium sulphide and manganese sulphate, de-coppering of the nickel electrolyte by stirring with the manganese sulphide and removal of Mn2+ ions from the de-coppered solution by oxidation with potassium permanganate to form manganese dioxide, which is precipitated. Laboratory studies show that the residual concentration of copper decreases with increasing manganese sulphide dosage, pH value, reaction temperature and reaction time. Using a manganese sulphide dosage of 1.4-fold of the theoretical value, a pH value of the electrolyte of 4-5, a reaction temperature of more than 60 degrees C and a reaction time in excess of 1 h, the concentration of copper decreases from 530 to 3 mg/l and the copper-nickel mass ratio in the residue reaches more than 15. Addition of the potassium permanganate reduces the concentration of freshly generated Mn2+ ions in the solution to 3 mg/l with a nickel loss of 0.1-0.5 g/l and the residual manganese concentration may be controlled at ca. 1 mg/l using an oxidising agent concentration of below 0.11 mol/l. An estimate is provided of the total cost/ton of nickel of the copper removal, namely US, A three-step process is described for the deep removal of copper from nickel electrolysis anode solutions comprising the preparation of manganese sulphide from sodium sulphide and manganese sulphate, de-coppering of the nickel electrolyte by stirring with the manganese sulphide and removal of Mn2+ ions from the de-coppered solution by oxidation with potassium permanganate to form manganese dioxide, which is precipitated. Laboratory studies show that the residual concentration of copper decreases with increasing manganese sulphide dosage, pH value, reaction temperature and reaction time. Using a manganese sulphide dosage of 1.4-fold of the theoretical value, a pH value of the electrolyte of 4-5, a reaction temperature of more than 60 degrees C and a reaction time in excess of 1 h, the concentration of copper decreases from 530 to 3 mg/l and the copper-nickel mass ratio in the residue reaches more than 15. Addition of the potassium permanganate reduces the concentration of freshly generated Mn2+ ions in the solution to 3 mg/l with a nickel loss of 0.1-0.5 g/l and the residual manganese concentration may be controlled at ca. 1 mg/l using an oxidising agent concentration of below 0.11 mol/l. An estimate is provided of the total cost/ton of nickel of the copper removal, namely US

The removal of impurities prior to the electrodeposition of Ni is discussed and a method described which involves the reduction of Cu2+ to Cu+, using sodium sulphite as reducing agent, followed by sorption using a strongly basic anion exchange resin. An orthogonal-design-of- experiments approach showed that the optimum conditions for Cu2+ reduction were a reducing agent dosage of 4.5 times the theoretical dosage and a reaction time of 0.5 h at 40 degrees C and pH 2.0. Ion exchange experiments showed that the breakthrough capacity decreased with an increase in the linear flow rate and increased with increasing height- to-radius ratio of the ion exchange resin column. The breakthrough capacity decreased with increasing initial Cu concentration. SO4(2-) and Ni concentrations did not change during the sorption process, indicating no loss of Ni during the process. Complete Cu desorption from the resin was achieved using NaCl solution containing 4 vol% H2O2 and a solution containing more than 100 g/l CuCl2 was obtained., The removal of impurities prior to the electrodeposition of Ni is discussed and a method described which involves the reduction of Cu2+ to Cu+, using sodium sulphite as reducing agent, followed by sorption using a strongly basic anion exchange resin. An orthogonal-design-of- experiments approach showed that the optimum conditions for Cu2+ reduction were a reducing agent dosage of 4.5 times the theoretical dosage and a reaction time of 0.5 h at 40 degrees C and pH 2.0. Ion exchange experiments showed that the breakthrough capacity decreased with an increase in the linear flow rate and increased with increasing height- to-radius ratio of the ion exchange resin column. The breakthrough capacity decreased with increasing initial Cu concentration. SO4(2-) and Ni concentrations did not change during the sorption process, indicating no loss of Ni during the process. Complete Cu desorption from the resin was achieved using NaCl solution containing 4 vol% H2O2 and a solution containing more than 100 g/l CuCl2 was obtained.

The effect of process variables was studied on the separation of Cu and Fe in the solvent extraction of dump bioleaching solutions containing low Cu2+/Fe3+ ratios from the Dexing mine in China. Optimum conditions were determined to be a LIX 984N concentration of 10%, organic/aqueous phase ratio of 1:1, initial pH value of the aqueous phase 1.5 and mixing time of 2 minutes. Stripping experiments showed that the use of H2SO4 solution resulted in the efficient recovery of Cu from the organic phase under the optimum conditions of an organic/aqueous phase ratio of 1:2 and 1.5 mol/l H2SO4 for 2 minutes., The effect of process variables was studied on the separation of Cu and Fe in the solvent extraction of dump bioleaching solutions containing low Cu2+/Fe3+ ratios from the Dexing mine in China. Optimum conditions were determined to be a LIX 984N concentration of 10%, organic/aqueous phase ratio of 1:1, initial pH value of the aqueous phase 1.5 and mixing time of 2 minutes. Stripping experiments showed that the use of H2SO4 solution resulted in the efficient recovery of Cu from the organic phase under the optimum conditions of an organic/aqueous phase ratio of 1:2 and 1.5 mol/l H2SO4 for 2 minutes.

The low-oxygen pressure leaching was investigated of slags obtained in the production of superfine and nanometre Ni powder by carbonylation. Optimum conditions for extracting Ni, Co and Cu and enrichment of precious metals were a cupric ion concentration of 5 g/l, pH 6, S coefficient of 1.4, oxygen pressure of 0.08 MPa, oxygen bubbling time of 20 min, liquid/solid ratio of 8:1, leaching time of 2 h and heating time of 2.5 h. The leaching rates of Ni and Co were more than 98% and that of Cu more than 97%. During the whole process, the leaching rates of Au and Ag were more than 99.9%, while other precious metals remain in the residue without any loss., The low-oxygen pressure leaching was investigated of slags obtained in the production of superfine and nanometre Ni powder by carbonylation. Optimum conditions for extracting Ni, Co and Cu and enrichment of precious metals were a cupric ion concentration of 5 g/l, pH 6, S coefficient of 1.4, oxygen pressure of 0.08 MPa, oxygen bubbling time of 20 min, liquid/solid ratio of 8:1, leaching time of 2 h and heating time of 2.5 h. The leaching rates of Ni and Co were more than 98% and that of Cu more than 97%. During the whole process, the leaching rates of Au and Ag were more than 99.9%, while other precious metals remain in the residue without any loss.

The method involves deoxidisation followed by ion exchange, the optimum deoxidisation conditions for Cu2+ being a sulphur coefficient of 4.5, pH 2.0, reaction time 0.5 h and temperature of 40 degrees C. The deoxidisation potential has a significant effect on work capability, the highest work capability occurring at a potential in the range 0.47-45 V. The results of ion exchange experiments show that the volume ratio increases with high-radius ratio, but remains unchanged when the high-radius ratio is 48.08. The work volume decreases with an increase in linear speed. With higher Cu concentrations the work capability decreases. There is no variation in the SO4(2-) concentration during the ion exchange process., The method involves deoxidisation followed by ion exchange, the optimum deoxidisation conditions for Cu2+ being a sulphur coefficient of 4.5, pH 2.0, reaction time 0.5 h and temperature of 40 degrees C. The deoxidisation potential has a significant effect on work capability, the highest work capability occurring at a potential in the range 0.47-45 V. The results of ion exchange experiments show that the volume ratio increases with high-radius ratio, but remains unchanged when the high-radius ratio is 48.08. The work volume decreases with an increase in linear speed. With higher Cu concentrations the work capability decreases. There is no variation in the SO4(2-) concentration during the ion exchange process.

There are abundant Lower Cambrian black shales associated with Ni-Mo ores in South China which contain jordisite as the main Mo component. The complex composition of the ore makes it difficult to extract the valuable components using conventional physical and chemical methods, and a new leach process has been proposed in which air is used as oxidant and S is oxidised to form SO4(2-), S2O3(2-) and SO3(2-), eliminating SO2 emissions. The co-existence of S2O3(2-) and SO3(2-) in acidified leach solution results in some of the Mo(VI) being reduced to Mo(V) to form the macromolecular polyion methylene blue which exhibits large size and high charge and a strong affinity with extractants and adsorbents. The adsorption behaviour of methylene blue on the macroporous weak basic anion exchange resin D301 was investigated. The results showed that optimum Mo adsorption was achieved using a feed solution with a pH in the range 3.5-4.5. The adsorption characteristics showed a good fit to the Freundlich equation. During adsorption the enthalpy and entropy changes were both positive and the free energy changes were negative at temperatures in the range 303-333 K, indicating that adsorption is a spontaneous and endothermic process and that higher temperatures are favourable. Kinetic data were well described by the double driving-force model and indicated that adsorption was controlled by intra-particle diffusion., There are abundant Lower Cambrian black shales associated with Ni-Mo ores in South China which contain jordisite as the main Mo component. The complex composition of the ore makes it difficult to extract the valuable components using conventional physical and chemical methods, and a new leach process has been proposed in which air is used as oxidant and S is oxidised to form SO4(2-), S2O3(2-) and SO3(2-), eliminating SO2 emissions. The co-existence of S2O3(2-) and SO3(2-) in acidified leach solution results in some of the Mo(VI) being reduced to Mo(V) to form the macromolecular polyion methylene blue which exhibits large size and high charge and a strong affinity with extractants and adsorbents. The adsorption behaviour of methylene blue on the macroporous weak basic anion exchange resin D301 was investigated. The results showed that optimum Mo adsorption was achieved using a feed solution with a pH in the range 3.5-4.5. The adsorption characteristics showed a good fit to the Freundlich equation. During adsorption the enthalpy and entropy changes were both positive and the free energy changes were negative at temperatures in the range 303-333 K, indicating that adsorption is a spontaneous and endothermic process and that higher temperatures are favourable. Kinetic data were well described by the double driving-force model and indicated that adsorption was controlled by intra-particle diffusion.

The selective extraction of Li from brine containing high Mg/Li ratios was investigated using a LiFePO4/FePO4 ion sieve material. A thermodynamic analysis was carried out of the selective adsorption of Na+, K+, Mg2+ and Li+ and the corresponding phi-pH diagrams for the Me(Li, Na, K, Mg)-Fe-P-H2O system at 298.15 K were plotted. For ion concentrations of 0.1 mol/l the redox potential of the system was controlled at values no higher than 0.36V versus SCE, the Fe3+ in FePO4 was reduced to Fe2+ and Li+ ions were simultaneously inserted in the FePO4 crystal lattice to form LiFePO4. KFePO4 and NaFePO4 were not formed until the potential of the system was reduced to 0.132 and 0.073 V, respectively. Li+ was preferentially adsorbed over Na+ and K+. Mg(0.5)FePO4 was not stable under the conditions studied ad Mg2+ was not adsorbed on the ion sieve. The results showed that the FEPO4 ion sieve could be used to selectively extract Li+ at redox potentials in the range 0.173-0.33 V. Li could be de-intercalated from LiFePO4 by increasing the potential of the system to above 0.33 V., The selective extraction of Li from brine containing high Mg/Li ratios was investigated using a LiFePO4/FePO4 ion sieve material. A thermodynamic analysis was carried out of the selective adsorption of Na+, K+, Mg2+ and Li+ and the corresponding phi-pH diagrams for the Me(Li, Na, K, Mg)-Fe-P-H2O system at 298.15 K were plotted. For ion concentrations of 0.1 mol/l the redox potential of the system was controlled at values no higher than 0.36V versus SCE, the Fe3+ in FePO4 was reduced to Fe2+ and Li+ ions were simultaneously inserted in the FePO4 crystal lattice to form LiFePO4. KFePO4 and NaFePO4 were not formed until the potential of the system was reduced to 0.132 and 0.073 V, respectively. Li+ was preferentially adsorbed over Na+ and K+. Mg(0.5)FePO4 was not stable under the conditions studied ad Mg2+ was not adsorbed on the ion sieve. The results showed that the FEPO4 ion sieve could be used to selectively extract Li+ at redox potentials in the range 0.173-0.33 V. Li could be de-intercalated from LiFePO4 by increasing the potential of the system to above 0.33 V.

The sodium hydroxide digestion of high-viscosity wolframite was investigated using a twin-screw extruder in order to overcome the disadvantages of high reaction temperature and low productivity associated with the conventional method. WO3 extraction of 99.13% and a WO3 concentration in the residue of 2.54% were obtained under optimum conditions of a mass ratio of ore to water of 2.67:1, NaOH dosage of 1.5 times stoichiometric, temperature of 120 degrees C, screw rotation speed of 180 r/min and reaction time of 2.5 h., The sodium hydroxide digestion of high-viscosity wolframite was investigated using a twin-screw extruder in order to overcome the disadvantages of high reaction temperature and low productivity associated with the conventional method. WO3 extraction of 99.13% and a WO3 concentration in the residue of 2.54% were obtained under optimum conditions of a mass ratio of ore to water of 2.67:1, NaOH dosage of 1.5 times stoichiometric, temperature of 120 degrees C, screw rotation speed of 180 r/min and reaction time of 2.5 h.

The leaching of garnierite was investigated using the pregnant solution obtained from the sulphuric acid leaching of limonitic ore and sodium jarosite precipitation. Ni, Mg and Fe leaching rates of 93.34%, 78.28% and 26.4%, respectively, were obtained in the acid leaching of garnierite using an ore size in the range 106-150 micrometres, final leaching pH of 1.3, leaching temperature and time of 95 degrees C for 3 h and stirring rate of 150 r/min. Leaching of garnierite using the pregnant solution from the leaching of limonitic ore resulted in Ni and Mg recoveries of 92% and more than 74%, respectively, using a Na molar ratio of 1.3 between NaSO4 additions and the Na jarosite precipitate. The Fe removal efficiency was more than 87%. Fe concentrations in the range 15.87-42.16 g/l had little effect on Ni and Mg recoveries, and the Fe concentration was reduced to less than 4 g/l., The leaching of garnierite was investigated using the pregnant solution obtained from the sulphuric acid leaching of limonitic ore and sodium jarosite precipitation. Ni, Mg and Fe leaching rates of 93.34%, 78.28% and 26.4%, respectively, were obtained in the acid leaching of garnierite using an ore size in the range 106-150 micrometres, final leaching pH of 1.3, leaching temperature and time of 95 degrees C for 3 h and stirring rate of 150 r/min. Leaching of garnierite using the pregnant solution from the leaching of limonitic ore resulted in Ni and Mg recoveries of 92% and more than 74%, respectively, using a Na molar ratio of 1.3 between NaSO4 additions and the Na jarosite precipitate. The Fe removal efficiency was more than 87%. Fe concentrations in the range 15.87-42.16 g/l had little effect on Ni and Mg recoveries, and the Fe concentration was reduced to less than 4 g/l.

The effect of gravity on the reaction engineering of a tubular reactor was studied by analysing the residence time distribution curves. The results showed that an upflow-feeding mode is better than a downflow-feeding mode, since the flow pattern of the fluid in the reactor is closer to plug flow conditions. Dynamic experiments using ion exchange columns with different height to diameter ratios were conducted using solutions with different WO3 concentrations. The breakthrough time decreased with increasing concentration for both the downflow-feeding and upflow-feeding modes. Upflow-feeding exhibited a longer breakthrough time and greater adsorption capacity, particularly at high WO3 concentrations., The effect of gravity on the reaction engineering of a tubular reactor was studied by analysing the residence time distribution curves. The results showed that an upflow-feeding mode is better than a downflow-feeding mode, since the flow pattern of the fluid in the reactor is closer to plug flow conditions. Dynamic experiments using ion exchange columns with different height to diameter ratios were conducted using solutions with different WO3 concentrations. The breakthrough time decreased with increasing concentration for both the downflow-feeding and upflow-feeding modes. Upflow-feeding exhibited a longer breakthrough time and greater adsorption capacity, particularly at high WO3 concentrations.