CN114560643A - Concrete admixture, preparation method and application thereof - Google Patents

Concrete admixture, preparation method and application thereof Download PDF

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Publication number
CN114560643A
CN114560643A CN202210241675.XA CN202210241675A CN114560643A CN 114560643 A CN114560643 A CN 114560643A CN 202210241675 A CN202210241675 A CN 202210241675A CN 114560643 A CN114560643 A CN 114560643A
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China
Prior art keywords
extract
kidney bean
beet pulp
root nodule
bean root
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CN202210241675.XA
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Inventor
杨凤玲
嵇银行
徐风广
侯海军
陆晓旺
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Yancheng Institute of Technology
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Yancheng Institute of Technology
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    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B24/00Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B20/00Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
    • C04B20/10Coating or impregnating
    • C04B20/12Multiple coating or impregnating
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2103/00Function or property of ingredients for mortars, concrete or artificial stone
    • C04B2103/20Retarders
    • C04B2103/22Set retarders
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/50Reuse, recycling or recovery technologies
    • Y02W30/91Use of waste materials as fillers for mortars or concrete

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Abstract

The invention discloses a concrete admixture, a preparation method and application thereof, wherein the concrete admixture comprises 30-35% by mass of beet pulp extract, 55-60% by mass of kidney bean root nodule extract and 10% by mass of adhesive; the method for obtaining the beet pulp extract comprises the following steps: pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving, adding an acid solution for soaking and acidolysis, and finally drying and pulverizing to obtain a beet pulp extract; the method for obtaining the kidney bean root nodule extract comprises the following steps: cleaning and drying kidney bean root nodule parts, crushing and sieving to obtain kidney bean root nodule powder, adding an alkali solution for soaking, centrifuging to obtain a supernatant, and finally drying to prepare powder to obtain a kidney bean root nodule extract; during preparation, the beet residue extract is used as a wall material, the kidney bean root nodule extract is used as a core material, and the core material is wrapped by the wall material through an adhesive, so that the concrete admixture is obtained. The invention has the functions of retarding coagulation and rust resistance, natural and pollution-free raw materials and simple preparation method.

Description

Concrete admixture, preparation method and application thereof
Technical Field
The invention relates to a building material, in particular to a concrete admixture, a preparation method and application thereof.
Background
In recent years, engineering accidents caused by too fast setting speed, too short setting time and poor durability of concrete materials have become endless. The addition of the rust inhibitor is an effective means for controlling the corrosion of the steel bars and enhancing the durability, and meanwhile, in order to delay the coagulation of the concrete, a retarder needs to be added, so that the cost is high. On the other hand, the conventional corrosion inhibitors comprise three types of inorganic, organic and hybrid corrosion inhibitors, wherein the inorganic corrosion inhibitor and the organic corrosion inhibitor are gradually eliminated due to factors such as carcinogenicity, toxicity and high environmental requirements, and the hybrid corrosion inhibitors which are nontoxic and have high corrosion resistance are more applied, but the synthesis of the hybrid corrosion inhibitors is complex and difficult to be applied in large scale in industrial production.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide an environment-friendly concrete admixture with retarding and rust-resisting functions, a second aim of the invention is to provide a preparation method of the concrete admixture, and a third aim of the invention is to provide application of the concrete admixture.
The technical scheme is as follows: the concrete admixture comprises, by mass, 30-35% of a beet pulp extract, 55-60% of a kidney bean root nodule extract and 10% of a binder; the method for obtaining the beet pulp extract comprises the following steps: pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving, adding an acid solution for soaking and acidolysis, and finally drying and pulverizing to obtain a beet pulp extract; the method for obtaining the kidney bean root nodule extract comprises the following steps: cleaning and drying kidney bean root nodule parts, crushing and sieving to obtain kidney bean root nodule powder, adding an alkali solution for soaking, centrifuging to obtain a supernatant, and finally drying to prepare powder to obtain the kidney bean root nodule extract.
In the invention, the two agricultural and sugar-making wastes of the beet pulp and the kidney bean root nodule are used as main raw materials, and the raw materials are natural and pollution-free, environment-friendly and low in cost. The beet pulp extract has stronger activity effect on the surfaces of cement particles and new phases of hydration products, can be adsorbed on the surfaces of the cement particles to form a layer of indissolvable film, plays a role of barrier to the hydration of the cement particles, and delays the hydration of the cement and the formation of a slurry structure; in addition, the cellulose in the beet pulp extract can also enhance the internal bonding of concreteThe effect of the force. The extract of root nodule of kidney bean contains abundant heterocyclic compounds such as flavonoid, which contains polar atoms or groups such as N, O, S, P, which can react with Fe2+The empty d track generates interaction of electron supply and electron receiving, and is effectively adsorbed on the surface of the steel bar, so that the electrochemical corrosion reaction of the steel bar is slowed down. Therefore, the concrete admixture of the invention has the composite action of initial retardation and later-stage rust resistance.
The invention also provides a preparation method of the concrete admixture, which comprises the following steps:
(1) obtaining a beet pulp extract: pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving, adding an acid solution for soaking and acidolysis, and finally drying and pulverizing to obtain a beet pulp extract;
(2) obtaining a kidney bean root nodule extract: cleaning and drying kidney bean root nodule parts, crushing and sieving to obtain kidney bean root nodule powder, adding an alkali solution for soaking, centrifuging to obtain a supernatant, and finally drying to prepare powder to obtain a kidney bean root nodule extract;
(3) weighing the raw materials according to the weight of claim 1;
(4) the concrete admixture is obtained by using the beet pulp extract as a wall material, using the kidney bean root nodule extract as a core material and wrapping the core material by the wall material through an adhesive.
The preparation process is simple, after the additive is added into the concrete, the effect of the retarding component in the wall material is exerted firstly, and after the wall material is fully exerted and the state of the concrete is stable, the rust-resisting component in the core material gradually seeps out of the adhesive, so that the durability of the concrete is continuously improved.
In step (1), nitric acid with the concentration of 0.1mol/L is adopted as the acid solution, and B ml of nitric acid is added to A g of beet pulp, wherein B is 3A.
Further, in the step (2), the alkali solution is a sodium hydroxide solution with a concentration of 0.7mol/L, and D ml of the sodium hydroxide solution is distributed to C g of kidney bean root nodule, wherein D is 7C.
Further, the adhesive employs MIEX resin.
Further, in the steps (1) and (2), vacuum drying is adopted during powder preparation by drying.
Further, the preparation method also comprises the step (5) of screening the concrete admixture by a centrifugal method to obtain admixture particles with the diameter of 1-3 mm.
The invention also provides an application of the concrete admixture, the concrete admixture is prepared by the preparation method, the concrete admixture is externally doped before the concrete is mixed by adding water, and the doping amount is 5-7% of the mass of the cementing material.
Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: (1) the raw materials belong to agricultural waste recycling, and the method is environment-friendly and low in cost; (2) the admixture can play a composite role in retarding the concrete at the initial stage and improving the durability at the later stage; (3) the invention is especially suitable for being used in the chloride environment, and improves the durability of the reinforced concrete structure, such as various seaports, sea-crossing bridges and other marine concrete projects.
Detailed Description
The present invention will be described in further detail below.
Example 1
The concrete admixture comprises 30% by mass of a beet pulp extract, 60% by mass of a kidney bean root nodule extract and 10% by mass of a binder. The method for obtaining the beet pulp extract comprises the following steps: taking 300g of beet pulp, pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving the beet pulp, adding 900ml of nitric acid of 0.1mol/L for soaking and acidolysis, and finally drying the beet pulp in vacuum at 60 ℃ for 2h to prepare powder to obtain the beet pulp extract. The method for obtaining the kidney bean root nodule extract comprises the following steps: the method comprises the steps of cleaning and drying 300g of kidney bean root nodule, crushing and sieving to obtain kidney bean root nodule powder, adding 2100ml of 0.7mol/L sodium hydroxide solution for soaking at 10000r/min, centrifuging for 3min, taking supernatant, and finally drying in vacuum at 70 ℃ for 3.5h to prepare powder to obtain the kidney bean root nodule extract. The method comprises the steps of taking a beet pulp extract as a wall material, wrapping a kidney bean root nodule extract as a core material by using an adhesive to obtain a concrete admixture, and screening admixture particles with the diameter of 2-3 mm by using a centrifugal method.
Example 2
The concrete admixture comprises 32% by mass of the beet pulp extract, 58% by mass of the kidney bean root nodule extract and 10% by mass of the binder. The method for obtaining the beet pulp extract comprises the following steps: taking 300g of beet pulp, pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving the beet pulp, adding 900ml of nitric acid of 0.1mol/L for soaking and acidolysis, and finally drying the beet pulp in vacuum at 60 ℃ for 2h to prepare powder to obtain the beet pulp extract. The method for obtaining the kidney bean root nodule extract comprises the following steps: the method comprises the steps of cleaning and drying 300g of kidney bean root nodule, crushing and sieving to obtain kidney bean root nodule powder, adding 2100ml of 0.7mol/L sodium hydroxide solution for soaking at 10000r/min, centrifuging for 3min, taking supernatant, and finally drying in vacuum at 70 ℃ for 3.5h to prepare powder to obtain the kidney bean root nodule extract. The method comprises the steps of taking a beet residue extract as a wall material, wrapping a kidney bean root nodule extract as a core material by using an adhesive to obtain a concrete admixture, and screening admixture particles with the diameter of 1-2 mm by using a centrifugal method.
Example 3
The concrete admixture comprises, by mass, 35% of a beet pulp extract, 55% of a kidney bean root nodule extract and 10% of a binder. The method for obtaining the beet pulp extract comprises the following steps: taking 300g of beet pulp, pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving the beet pulp, adding 900ml of nitric acid of 0.1mol/L for soaking and acidolysis, and finally drying the beet pulp in vacuum at 60 ℃ for 2h to prepare powder to obtain the beet pulp extract. The method for obtaining the kidney bean root nodule extract comprises the following steps: the method comprises the steps of cleaning and drying 300g of kidney bean root nodule, crushing and sieving to obtain kidney bean root nodule powder, adding 2100ml of 0.7mol/L sodium hydroxide solution for soaking at 10000r/min, centrifuging for 3min, taking supernatant, and finally drying in vacuum at 70 ℃ for 3.5h to prepare powder to obtain the kidney bean root nodule extract. The method comprises the steps of taking a beet pulp extract as a wall material, wrapping a kidney bean root nodule extract as a core material by using an adhesive to obtain a concrete admixture, and screening admixture particles with the diameter of 1-3 mm by using a centrifugal method.
The working effect of the concrete admixture of the invention in concrete is verified by tests below.
Test one, strength test
The formed fine aggregate concrete test piece has the size of 40mm by 160mm, the cement is 42.5-grade ordinary portland cement, the water cement ratio is 0.43, the ash sand ratio is 0.46, the concrete admixture is respectively added with 5 percent, 6 percent and 7 percent (relative to the mass of the cement), the blank control without the admixture is set, and the compressive strength of 3d, 7d and 28d is measured after forming. The test results are shown in Table 1.
TABLE 1 concrete compression Strength test results
Figure BDA0003542383720000031
As can be seen from Table 1, the compressive strength of the fine aggregate concrete was not significantly changed by the addition of the concrete admixtures of examples 1, 2 and 3, indicating that the addition of the concrete admixtures did not affect the strength of the concrete.
Experiment two, simulation concrete pore solution reinforcing bar sample electrochemistry impedance test
Cutting the HPB235 steel bar with the diameter of 10mm into short bars with the length of 10mm, sealing the columnar side surfaces of the short bars by using epoxy resin, and sequentially polishing the short bars to a mirror surface by using No. 600, No. 1000 and No. 2000 metallographic abrasive paper by using the end surfaces as working surfaces to obtain the required working electrode. A saturated calcium hydroxide solution containing 2.5% NaCl was prepared. The concrete admixture prepared in the three embodiments is added into a saturated calcium hydroxide solution containing 2.5% of NaCl according to the solution amount of 6%, the polished steel bar is placed in the saturated calcium hydroxide solution, the saturated calcium hydroxide solution is sealed, and electrochemical tests of self-corrosion potential and corrosion current density are carried out after 24 hours. Meanwhile, the corrosion performance of the sample by the 2.5% NaCl-containing saturated calcium hydroxide solution without the additive was tested as a control.
The test result shows that the corrosion potential and the corrosion current density of the blank control group are-514 mV vs SCE and 1.921 muA/cm respectively2. The corrosion potentials of the samples to which the concrete admixtures of examples 1, 2 and 3 were added were shifted in positive levels to-419 mV vs SCE, -433mV vs SCE and-441 mV vs SCE, respectively, as compared with the blank control group. The corrosion current density is also obviously reduced, respectivelyIs 0.107 muA/cm2、0.165μA/cm2、0.182μA/cm2. The corrosion potential of the sample added with the concrete admixture of the invention is shifted positively, which shows that the corrosion trend of the steel bar is reduced; the decrease of the corrosion current density indicates the decrease of the corrosion rate of the steel bar. The result shows that the concrete admixture has obvious rust resistance effect.

Claims (8)

1. A concrete admixture is characterized in that: by mass, the fertilizer comprises 30-35% of beet pulp extract, 55-60% of kidney bean root nodule extract and 10% of adhesive; the method for obtaining the beet pulp extract comprises the following steps: pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving, adding an acid solution for soaking and acidolysis, and finally drying and pulverizing to obtain a beet pulp extract; the method for obtaining the kidney bean root nodule extract comprises the following steps: cleaning and drying kidney bean root nodule parts, crushing and sieving to obtain kidney bean root nodule powder, adding an alkali solution for soaking, centrifuging to obtain a supernatant, and finally drying to prepare powder to obtain the kidney bean root nodule extract.
2. A method for producing the concrete admixture according to claim 1, characterized by comprising: the method comprises the following steps:
(1) obtaining a beet pulp extract: pretreating the beet pulp by using sodium sulfite to remove lignin in the beet pulp, crushing and sieving, adding an acid solution for soaking and acidolysis, and finally drying and pulverizing to obtain a beet pulp extract;
(2) obtaining a kidney bean nodule extract: cleaning and drying kidney bean root nodule parts, crushing and sieving to obtain kidney bean root nodule powder, adding an alkali solution for soaking, centrifuging to obtain a supernatant, and finally drying to prepare powder to obtain a kidney bean root nodule extract;
(3) weighing the raw materials according to the weight of claim 1;
(4) the concrete admixture is obtained by using the beet pulp extract as a wall material, using the kidney bean root nodule extract as a core material and wrapping the core material by the wall material through an adhesive.
3. The method of claim 2, wherein: in the step (1), nitric acid with the concentration of 0.1mol/L is adopted as the acid solution, A g of beet pulp is mixed with B ml of nitric acid, and B is 3A.
4. The method of claim 2, wherein: in the step (2), the aqueous alkali is 0.7mol/L sodium hydroxide solution, D ml sodium hydroxide solution is distributed to C g kidney bean root nodule, and D is 7C.
5. The method of claim 2, wherein: the adhesive is MIEX resin.
6. The method of claim 2, wherein: in the steps (1) and (2), vacuum drying is adopted during drying and powdering.
7. The production method according to any one of claims 2 to 6, characterized in that: and (5) screening the concrete admixture by a centrifugal method to obtain admixture particles with the diameter of 1-3 mm.
8. The application of the concrete admixture is characterized in that: the concrete admixture is prepared by the preparation method of any one of claims 2 to 7, and is externally mixed before the concrete is mixed by adding water, wherein the mixing amount is 5 to 7 percent of the mass of the cementing material.
CN202210241675.XA 2022-03-11 2022-03-11 Concrete admixture, preparation method and application thereof Pending CN114560643A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB654767A (en) * 1947-03-17 1951-06-27 Danske Sukkerfab Improvements relating to the production of jellyfying pectins
CN108516726A (en) * 2018-04-24 2018-09-11 常州五荣化工有限公司 A kind of preparation method of reinforcing steel bar corrosion inhibitor
CN109437636A (en) * 2018-11-13 2019-03-08 河海大学 A kind of reinforcing steel bar corrosion inhibitor and methods for making and using same fallen leaves using discarded plant

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB654767A (en) * 1947-03-17 1951-06-27 Danske Sukkerfab Improvements relating to the production of jellyfying pectins
CN108516726A (en) * 2018-04-24 2018-09-11 常州五荣化工有限公司 A kind of preparation method of reinforcing steel bar corrosion inhibitor
CN109437636A (en) * 2018-11-13 2019-03-08 河海大学 A kind of reinforcing steel bar corrosion inhibitor and methods for making and using same fallen leaves using discarded plant

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
D R GUSTI* ETC.: "Exploration of coffee bean husks waste as an eco-environmentally friendly corrosion inhibitor on mild steel in sulphuric acid solutions", 《THE 4TH INTERNATIONAL SYMPOSIUM ON GREEN TECHNOLOGY FOR VALUE CHAINS 2019》 *
王何柱 等: "不同花色芸豆种皮酚类化合物组成及抗氧化活性", 《食品科学》 *
陈泊韬: "甜菜渣成分在浓硝酸和酶作用下的变化", 《现代食品科技》 *

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