93 results about "Nitrosation" patented technology

Systems and methods for producing ammonium nitrate are disclosed herein. Exemplary systems can comprise a bioreactor positioned to receive a feed including ammonia. The bioreactor can hold a liquid solution including (i) an ammonia oxidizing bacteria (AOB) and (ii) a nitrite oxidizing bacteria (NOB). The AOB can facilitate oxidation of the ammonia to produce a nitrite at a nitritation rate and the NOB can facilitate oxidation of the nitrite at a nitratation rate. Thus, the bioreactor can produce a mixed liquor comprising a nitrate biologically. The system can further comprise a filter positioned to receive the mixed liquor and produce a permeate and a sludge. A sensor can measure the concentration of the liquid solution of the bioreactor, and a controller coupled to the sensor can regulate the mass flow of nitrogen and / or phosphorus of the bioreactor feed based on the measured concentration of the liquid solution.

The application provides a synthesis method of p-benzoquinone dioxime. The synthesis method comprises the following steps: (1) adding solid acid into an ethanol solution of phenol to obtain a mixed solution A, then vacuumizing and filling with inert gas; dissolving nitrite into ethanol, uniformly mixing to obtain an ethanol solution of nitrite, then vacuumizing and filling with inert gas; in an inert gas atmosphere, adding the ethanol solution of nitrite into the mixed solution A dropwise to perform nitrosation reaction, to obtain a reaction liquid B; in the inert gas atmosphere, adding an ethanol solution of hydroxylamine into the obtained reaction liquid B to perform oximation reaction; after the reaction is completed, filtering the obtained reaction liquid C, performing reduced pressure distillation on the obtained filtrate, and performing washing, filtering and drying on the obtained residual liquid of the reduced pressure distillation, to obtain p-benzoquinone dioxime. The method provided by the application reduces the occurrence of side reactions, improves the conversion rate of the reaction, and improves the yield and purity of p-benzoquinone dioxime.

The present application relates to sewage treatment technical field, especially a kind of composite biological additive for high-nitrogen sewage advanced treatment.The present application obtains a high-quality fermentation liquor by using specific enzymolysis sequence enzymolysis agricultural derivative, wherein it contains more reducing sugar and organic small molecule acid, and COD equivalent is extremely high, is 2~5 times of the carbon source COD used by conventional sewage plant, and has excellent effect when used as biological carbon source for sewage treatment;Meanwhile, the fermentation liquor is compounded and adjusted with AOB bacterial agent to obtain composite biological additive, the composite biological additive can provide sufficient high-quality nutrient ingredients for denitrifying bacteria, and also inoculate AOB bacteria for sewage treatment system, so that AOB bacteria in the system gradually develop into main nitrosation bacteria group, and have excellent enhanced denitrification effect on high-nitrogen sewage, and have wide application prospect.

The application provides a treatment system and method for low-carbon high-ammonia-nitrogen wastewater, which comprises a hydrolysis acidification tank, a nitritation / anaerobic ammonia oxidation / denitrification chamber and an aerobic MBR tank connected in sequence; the hydrolysis acidification tank is provided with a wastewater inlet, and is connected with the bottom of the nitritation reaction zone; the aerobic MBR tank is provided with a water outlet connected with the outside; the nitritation / anaerobic ammonia oxidation / denitrification chamber comprises two parts separated by a partition, the inside is the nitritation reaction zone, and the outside is the anaerobic ammonia oxidation and denitrification reaction zone, and the water flow can pass through the top of the partition. The application controls the aeration amount of the MBR aeration tank and the reflux ratio, controls the dissolved oxygen of the nitritation / anaerobic ammonia oxidation / denitrification chamber in the required range, stably creates the environment required for nitritation and anaerobic ammonia oxidation, simultaneously performs the nitritation, anaerobic ammonia oxidation and denitrification reaction in the integrated anaerobic ammonia oxidation tank, removes total nitrogen and part of organic matters, can not only efficiently remove total nitrogen and organic matters, but also save the aeration amount and energy.

The invention discloses an engineering continuous preparation method of 3-amino-4-amidoxime furazan, which is characterized in that engineering synthesis of 3-amino-4-amidoxime furazan is technically verified and optimized by adopting a continuous flow micro-channel reactor and a dynamic tubular reactor technology, and malononitrile is used as a starting raw material to react in the micro-channel reactor; the preparation method comprises the following steps: carrying out nitrosation and oximation to obtain a trioxime solution, conveying trioxime and a cyclization solution to a dynamic tubular reactor, heating to a certain temperature, reacting and curing, overflowing into a collection tank through the tubular reactor, adjusting the pH value of a reaction solution, cooling, filtering, washing with water, and drying to obtain the 3-amino-4-amidoxime furazan. The AAOF engineering manufacturing process scheme is provided, AAOF kilogram-level engineering preparation under automatic control is achieved, the problems of material precipitation, heat exchange and the like in an intermittent production mode are solved, and the synthesis efficiency and the synthesis safety are greatly improved.

The invention discloses an epinephrine drug nitrosamine impurity as well as a preparation method and application thereof. According to the method, an epinephrine drug is taken as a raw material, hydroxyl is protected through a silane protecting group, the protected hydroxyl and a nitrosation reagent are subjected to a selective nitrosation reaction, and then the target nitrosamine impurity is obtained through a deprotection reaction. According to the method, the high-purity nitrosamine impurity of the epinephrine medicine can be prepared and used as a reference substance for qualitative and content detection of the nitrosamine impurity in the production process of raw materials and medicines, so that it is ensured that the epinephrine raw material medicine and preparations meet the medicinal standard; the method has important significance in improving the quality of epinephrine drugs and guaranteeing the medication safety.

The invention discloses a method for treating industrial wastewater rich in high-concentration nitric acid, and belongs to the technical field of range, and in the method, the treatment efficiency of high-concentration nitric acid and ammonia nitrogen wastewater is remarkably improved through the synergistic effect of catalytic oxidation and biological denitrification. In the catalytic oxidation stage, a Fe-Cu bimetallic catalyst is adopted to directionally regulate and control the nitrogen form, nitrate is reduced while part of ammonia nitrogen is oxidized into nitrite, nitrosation accumulation is formed, and the follow-up biological treatment load is greatly reduced. In the biological denitrification stage, through a short-cut denitrification and anaerobic ammonia oxidation coupling path, ammonia is directly used as an electron donor to react with nitrite derivatives to generate nitrogen, not only is the carbon source demand reduced by 60% or above, but also the sludge yield is reduced by 40%, the comprehensive operation cost is saved by 50% or above compared with that of a traditional process, and no secondary pollutants are generated in the whole process.

The utility model discloses a short-cut nitrification coupling anaerobic ammonia oxidation integrated reactor, a perforated plate is arranged in the reactor, and a first part for short-cut nitrification and a second part for anaerobic ammonia oxidation are respectively distributed on the upper side and the lower side of the perforated plate; sludge of nitrite bacteria is attached to the interior of the first part through a first filler so as to fix aerobic bacteria, and the first part is connected with an aeration source; anaerobic ammonia oxidizing bacteria are fixed in the second part through a second filler; the size of the filler is greater than the hole size of the perforated plate; the second part is provided with a muddy water backflow and separation module; the muddy water backflow and separation module comprises the muddy water separation area and a sludge backflow area which is integrally connected with the muddy water separation area; a water outlet pipe is connected into the mud-water separation area and is used for separating and discharging aged sludge. The reactor can stabilize the growth of dominant bacteria and improve the denitrification treatment effect.

The present invention discloses a sewage treatment method based on a PN / A coupled biochar SPD process. After the sewage enters the front-end SPD fixed bed through the front-end inlet / outlet channel, the organic matter in the sewage is removed by the adsorption effect of the biochar bricks inside the sewage; then, after entering the PN / A reactor through the front-end upflow / downflow trough, the sewage is denitrified by the nitrite sludge and fully autotrophic denitrification granular sludge inoculated therein; then, after entering the rear-end SPD fixed bed through the rear-end upflow / downflow trough, the denitrifying bacteria use the organic matter adsorbed by the biochar bricks inside as a carbon source to remove residual nitrates in the sewage. Finally, the effluent is discharged through the rear-end inlet / outlet channel. The present invention determines whether the biochar has reached adsorption saturation by real-time detection of the DO concentration and nitrate nitrogen concentration in the PN / A reactor, and dynamically adjusts the inlet and outlet directions to achieve the purpose of repeatedly utilizing the organic matter adsorbed by the biochar, effectively solving the problems of high carbon source cost for deep denitrification and increased amount of residual sludge.

Nitric oxide precursors for providing nitric oxide are provided. The nitric oxide precursors comprise a reaction product of a thiolactone, a primary amine, and a nitrosating compound. The nitric oxide precursors are capable of decomposing to form nitric oxide.

This invention relates to the field of wastewater biological treatment technology, specifically to a device and method for improving the autotrophic denitrification performance of a MABR reactor. It employs a composite membrane module combining a curtain-type silica gel filament membrane with excellent oxygen permeability with a spatial three-dimensional mesh packing material that facilitates the attachment of anaerobic ammonia-oxidizing bacteria, thereby coupling part of the nitrification reaction with the anaerobic ammonia oxidation reaction. Through the circulating reaction zone and membrane reaction zone within the reactor, nitrate nitrogen generated by anaerobic ammonia oxidation and excess nitrite nitrogen during instability adjustment are circulated and removed, thus improving the total nitrogen removal efficiency of the reactor. By adding appropriate amounts of sodium nitrite solution at appropriate times, the free nitrite concentration in the reactor mixture is increased. Simultaneously, the intermittent aeration ratio of the MABR is controlled to achieve synergistic inhibition of nitrite-oxidizing bacteria activity by low dissolved oxygen and high free nitrite, allowing the unstable short-range nitrification reaction to recover and improving the autotrophic denitrification performance of the reactor.

The invention provides a rapid biofilm culturing system and method for an autotrophic nitrogen removal membrane aeration biofilm reactor. The system comprises at least two stages of first biofilm culturing devices and second biofilm culturing devices which are connected in series, at least one first biofilm culturing device comprises a nitrosation inoculation carrier; at the same time, at least one second biofilm culturing device comprises an anaerobic ammonia oxidation inoculation carrier; conducting film assemblies to be subjected to film hanging are sequentially placed in the first film hanging device and the second film hanging device under constant micro-voltage to be subjected to film hanging; the water inlet assembly comprises a first water tank and a second water tank; ammonia nitrogen inlet water is contained in the first water tank, and the first water tank is connected with the first biofilm culturing device and the second biofilm culturing device; and the second water tank contains nitrite inlet water and is connected with the second biofilm culturing device. According to the invention, the conducting film assembly to be subjected to film hanging is subjected to layered film hanging in the first film hanging device and the second film hanging device respectively, so that rapid film hanging and starting of the MABR-PN / A process are realized.

The invention provides a nitrite quantitative detection method based on surface enhanced Raman spectroscopy, relates to the technical field of surface enhanced Raman spectroscopy, and constructs a self-correcting SERS substrate through a three-phase liquid-liquid interface co-assembly technology. In the experiment process, a sample to be detected is mixed with a thiobarbituric acid solution, the mixture is adjusted to be acidic, NO2 <-> and thiobarbituric acid are subjected to an S-nitrosation reaction, and S-nitroso mercaptan is generated. And then, immersing the self-correcting SERS substrate into a reaction solution, so that the substrate adsorbs the generated S-nitroso mercaptan, and further, a Raman signal is enhanced. After soaking is completed, the substrate is taken out and dried, finally, a Raman signal is collected through a Raman spectrometer, and the concentration of NO2 <-> is accurately analyzed through the change of the signal intensity. According to the technical scheme, rapid and high-sensitivity detection of NO2 <-> is achieved, good selectivity and anti-interference capacity are achieved, and the method is widely suitable for detection requirements of multiple fields such as environment monitoring and food safety.

The present application relates to sewage biological treatment technical field, provide a kind of ammonia nitrogen wastewater short path nitrification method and application.The method includes: S100, mature autotrophic short path nitrification sludge is inoculated into reactor, and first mixed liquor is obtained;S200, water containing ammonium salt, bicarbonate and phosphate is transported into reactor by water inlet pump;S300, first mixed liquor is mixed with water by stirrer, and aeration reaction is carried out, and second mixed liquor is obtained;S400, stop stirring, aeration and pH control to second mixed liquor, carry out solid-liquid separation, and obtain treated water and sludge;S500, enable water pump, and treated water is uniformly discharged;S600, repeat steps S200-S500, add cerium chloride solution, and carry out long-term operation.The present application uses low concentration cerium to selectively enrich endogenous heterotrophic nitrosobacteria, and cooperates with autotrophic nitrosobacteria by cerium ion, to improve the accumulation rate of nitrite.

The invention provides a rapid biofilm culturing method and equipment for a membrane aeration biofilm reactor. The rapid biofilm culturing method of the membrane aeration biofilm reactor comprises the following steps: performing first-stage biofilm culturing on a nitrosation carrier and a membrane assembly in an inoculation container, and performing second-stage biofilm culturing on a nitrosation-anaerobic ammonia oxidation carrier and the membrane assembly after the first-stage biofilm culturing in the inoculation container, and carrying out third-stage biofilm culturing on the anaerobic ammonia oxidation carrier and the membrane component subjected to the second-stage biofilm culturing in the inoculation container. According to the rapid biofilm culturing method of the membrane aeration biofilm reactor, the nitrosation carrier, the nitrosation-anaerobic ammonia oxidation carrier and the anaerobic ammonia oxidation carrier are sequentially subjected to biofilm culturing on the membrane assembly in stages, so that the biofilm is formed on the surface of the membrane assembly, and each carrier has short biofilm culturing time, so that the total biofilm culturing time of the biofilm is short; and the state of the biological membrane attached to the biological membrane is uniform, compact and stable, and the community structure of the target flora of the biological membrane is stable.

A nitric oxide precursor for providing nitric oxide is provided. The nitric oxide precursor comprises a reaction product of a thiolactone, a primary amine, and a nitrosating compound. The nitric oxide precursor is capable of decomposing to form nitric oxide.

Systems and methods for producing ammonium nitrate are disclosed herein. Exemplary systems can comprise a bioreactor positioned to receive a feed including ammonia. The bioreactor can hold a liquid solution including (i) an ammonia oxidizing bacteria (AOB) and (ii) a nitrite oxidizing bacteria (NOB). The AOB can facilitate oxidation of the ammonia to produce a nitrite at a nitritation rate and the NOB can facilitate oxidation of the nitrite at a nitratation rate. Thus, the bioreactor can produce a mixed liquor comprising a nitrate biologically. The system can further comprise a filter positioned to receive the mixed liquor and produce a permeate and a sludge. A sensor can measure the concentration of the liquid solution of the bioreactor, and a controller coupled to the sensor can regulate the mass flow of nitrogen and / or phosphorus of the bioreactor feed based on the measured concentration of the liquid solution.

The invention provides a trace hydroxyl radical determination method based on sodium nitrite color development and application, and belongs to the field of chemometrics. The method comprises the following steps: constructing two reaction systems, namely a system based on a mixed solution of 2, 3-DHBA and 2, 5-DHBA and a. OH sample determination reaction system based on H2O2 concentration regulation, reacting under specific conditions, and adding an HCl solution to terminate the reaction; the method comprises the following steps: measuring the absorbance, establishing a calibration equation according to the absorbance of a mixed solution system of 2, 3-DHBA and 2, 5-DHBA, establishing a calculation equation according to the absorbance of a H2O2 concentration regulation and control system, establishing a reference equation in combination with an electron spin resonance measurement result, verifying the accuracy of the method through data crosslinking, and finally substituting the accuracy into a related equation to obtain the concentration of. OH in a sample to be detected. According to the method, the nitrosation capacity of NaNO2 is combined with hydroxylation capture of DHBA, and a unique color development path is constructed. The method has the characteristics of simplicity and convenience in operation, low cost and high sensitivity, and is suitable for quantitative analysis of. OH in stoichiometry.

The present application relates to wastewater treatment technical field, especially to a kind of high organic matter high ammonia wastewater's whole process processing device and processing method.The present application provides a kind of high organic matter high ammonia wastewater's whole process processing device, including sequentially connected anaerobic tower, short-path denitrification-anaerobic ammonia oxidation pool, nitrosation-anaerobic ammonia oxidation pool, denitrification swing pool, intermediate sedimentation tank, denitrification tank, nitrification carbon removal pool and final sedimentation tank.The processing device is placed in front of short-path denitrification-anaerobic ammonia oxidation pool, effectively avoid the influence of organic matter on subsequent autotrophic denitrification microorganism denitrification.And the processing device treats high organic matter high ammonia wastewater with the characteristics of low cost, high efficiency.

The present invention discloses a method for synthesizing a nitrosamine organic compound. The method comprises reacting a compound having a structure represented by formula (I) with nitromethane under electrochemical action to obtain a nitrosamine organic compound having a structure represented by formula (II). The method achieves nitrosation of a secondary amine through a one-step reaction under mild reaction conditions. The obtained product has a high reaction yield and is valuable for reuse as a pharmaceutical. This method therefore has excellent application prospects.

The invention relates to the technical field of biological medicines, and in particular relates to a synthetic method of a tubulin inhibitor (Sabizabulin). According to the method, 3, 4, 5-trimethoxyacetophenone (compound 1) is taken as a starting raw material, and nucleophilic addition and methylation, oxidation, addition elimination, nitrosation, cyclization and methylthio removal are carried out, so that the Sabizabulin inhibitor is obtained. The synthetic route is safe in reaction, mild in condition, free of synthetic protecting groups, simple to operate and relatively high in yield. The method disclosed by the invention lays a foundation for the industrial preparation of the Sabizabulin.

The invention relates to the technical field of microbial infection treatment and molecular biology, and provides a method for inhibiting formation of a staphylococcus aureus biofilm, which is realized by inhibiting nitrosation modification of MgrA protein in staphylococcus aureus so as to inhibit formation of the biofilm. The inhibitor is nitric oxide synthase and is used for inhibiting nitrosation modification of the MgrA protein; the nitrosation modification for inhibiting the MgrA protein is realized by applying a nitric oxide synthase (NOS) inhibitor; the invention reveals that the staphylococcus aureus endogenous nitric oxide can promote the formation of a biofilm by modifying and regulating the 12th cysteine of the protein MgrA for the first time; based on the target spot, research proves that the MgrA modification level can be effectively reduced and the removal of the biofilm can be enhanced through multiple means such as gene mutation, NOS inhibitor or combination of the NOS inhibitor and antibiotics, and a new strategy and a potential drug development approach are provided for preventing and treating staphylococcus aureus intractable biofilm infection.

Compositions and methods are presented for nitric oxide precursors that release nitric oxide upon decomposition. The nitric oxide precursors include the reaction products of thiol-containing alcohols, silanes, and nitrosated compounds, allowing for technically simple (e.g., solventless, one-pot synthesis) and flexible synthesis of nitric oxide precursors and mixtures thereof, and allowing for control of the nitric oxide release rate (e.g., via the use of primary, secondary, and / or tertiary nitrosothiols, alone or in combination with additives).

The application relates to a device for controlling short-range nitrification and denitrification of embedded particles, which comprises a water inlet module, a constant-temperature heating module, an alkali adding module, a free nitrous acid real-time monitoring module, an aeration fan, an aerobic tank, an anoxic tank, an MBR tank, a water outlet module and a sludge discharge module; the water inlet module, the constant-temperature heating module and the free nitrous acid real-time monitoring module are connected with the aerobic tank; the alkali adding module is connected with the anoxic tank; the aeration fan is connected with the bottom of the aerobic tank and the MBR tank respectively; the MBR tank is further provided with the water outlet module and the sludge discharge module. The device has the beneficial effects that the device controls the FNA in the aerobic tank at a high level through backflow of the aerobic tank, inhibits the activity of NOB in the embedded particles, makes ammonia nitrogen oxidation stay in the nitrosation stage, realizes the stability of short-range nitrification and denitrification of the embedded particles, the total nitrogen removal rate of the system reaches more than 85%, and the energy consumption can be reduced by about 15%.

The application discloses a method for preparing high-purity 6-nitro-1,2-diazoxy-4-naphthalenesulfonic acid, and relates to the technical field of dye intermediates. The method comprises the following steps: taking beta-naphthol as a starting material, and sequentially performing nitrosation, reduction, transposition sulfonation, diazotization and nitration reactions to obtain the final target product. In the process of preparing 1-amino-2-naphthol-4-sulfonic acid by reducing and transposition sulfonating 1-nitroso-2-naphthol, a proper amount of an auxiliary is timely used, the reduction efficiency is improved, and the dispersibility of the substrate in the system is enhanced, so that the yield and purity of the finally prepared 6-nitro-1,2-diazoxy-4-naphthalenesulfonic acid are improved.

The invention discloses N-nitroso tadalafil and a synthesis method and application thereof, and the synthesis method comprises the following steps: adding tadalafil into a reaction container, then adding a solvent for dissolving, balancing the system at (-20) DEG C to (-2) DEG C for 8-16 minutes, adding a nitrosation reagent for sealed reaction, after the reaction is finished, extracting, drying, concentrating, and carrying out column chromatography to obtain the N-nitroso tadalafil. The target product N-nitroso tadalafil is obtained. The N-nitroso tadalafil synthesis method is simple and convenient in process, the obtained product is high in purity, a reliable standard substance can be provided for tadalafil product quality research and analysis method development and verification, and the method has good popularization value.

The application belongs to the technical field of soil treatment and sewage treatment, and particularly relates to application of 5-methylisoxazole nitrification inhibitor and a method for inhibiting nitrification. The application comprises application in inhibiting nitrification activity of ammonia-oxidizing bacteria and in inhibiting nitrification activity of nitrite-oxidizing bacteria. Through a large number of researches and experiments, the application finds nitrification inhibition activity of 5-methylisoxazole, and realizes full-path regulation of nitrification. Experiments show that the compound can inhibit ammonia oxidation activity of a typical nitrifying strain at a low dose (>=0.01‰w / v), and can effectively inhibit activity of nitrite-oxidizing bacteria at a concentration lower than 0.1‰m / v. The aqueous solution of the compound has a neutral pH, and has no significant inhibitory effect on non-target heterotrophic microorganisms, and has high selectivity and environmental friendliness.

Compositions and methods for decomposing nitric oxide precursors to release nitric oxide are provided. The nitric oxide precursors comprise the reaction product of a thiol-containing alcohol, a silane, and a nitrosation compound that allows for technically simple (e.g., solvent-free one-pot synthesis) and flexible synthesis of nitric oxide precursors and mixtures thereof that allow for controlled release rates of nitric oxide (e.g., for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, for example, or for example, for example, for example, for example. The use of primary, secondary, and / or tertiary nitrosothiol by use alone or in combination with additives).

This invention relates to a bis-Sydney ketone terminal compound, its preparation method, and its application, belonging to the field of organic synthesis technology. It solves the problems of existing synthetic methods involving multiple reaction steps, low reaction efficiency, low yield, and difficulty in efficiently and massively synthesizing bis-Sydney ketone terminal compounds. The preparation method synthesizes the bis-Sydney ketone terminal compound through a three-step organic reaction, including the following steps: Step 1: Dissolving a primary amino compound, a secondary amination reagent, and a base in a solvent to undergo a secondary amination reaction, followed by recrystallization to obtain a first intermediate; Step 2: Dissolving the first intermediate, adding a hydrolysis reagent to undergo a hydrolysis reaction, adjusting the solution to acidity, and filtering to obtain a second intermediate; Step 3: Dissolving the second intermediate, adding a nitrosating reagent to undergo a nitrosation reaction, adding a dehydrating agent to the reaction system to undergo an internal cyclization reaction, and post-treatment to obtain the bis-Sydney ketone terminal compound.

The application discloses an ammonia-nitrogen wastewater treatment method and system based on anaerobic ammonia oxidation, and the treatment method comprises successively performing a dissimilatory iron reduction treatment, a nitrosation treatment on ammonia-nitrogen wastewater, and performing anaerobic ammonia oxidation treatment on the wastewater after the nitrosation treatment by introducing the wastewater from the top of an anaerobic ammonia oxidation reactor, and performing Fenton treatment, wherein the solid phase obtained after the Fenton treatment is returned to the dissimilatory iron reduction treatment. The system for realizing the treatment method comprises a dissimilatory iron reduction reaction tank, a nitrosation reaction tank, an inverted anaerobic ammonia oxidation reactor, a Fenton reaction tank and a biological aerated filter which are connected in sequence. The ammonia-nitrogen wastewater treatment method based on anaerobic ammonia oxidation has the advantages of simple process, convenient operation, short starting time, low treatment cost, high treatment efficiency, good treatment effect, wide water quality application range, good running stability, full-quantitative disposal and the like, can effectively purify various kinds of refractory high-ammonia-nitrogen wastewater, has high use value and good application prospect.